Search/Browse Help - Keyword Search

About Keyword Search

Keyword Search provides a single search box to find words and phrases anywhere in the LC Catalog record or in title, author/creator, or subject fields. Search results are returned by relevance. An Expert option is available from the Keyword Search menu for searchers who prefer command-driven queries.

The Keyword Search shortcut URL is: https://catalog.loc.gov/keyword

Keyword Search can be helpful if you're looking for specific items but are unsure, for example, of the complete name of an author/creator or the first words of a title. Drop-down menu options let you filter your keywords by title, author/creator, and subject. More specific keyword filtering is available with Advanced Search. You can also toggle open context-sensitive search tips or click Search/Browse Help from either the menu at the top of your screen or the Help link at the bottom of your screen.

Keyword (ALL)

Finds all words in any order or exact phrases located anywhere in the record. Use Keyword (ALL) when you're not sure what fields contain the words or phrases you need or when your searches return no results using other search types.

Keyword (TITLE)

Finds all words or phrases in title areas of the record. Title areas include main titles, uniform titles, alternate titles, titles in links, and titles in tables of contents. Use Keyword (TITLE) when you know several words from the title but are unsure in what order the words appear.

Keyword (AUTHOR/CREATOR)

Finds all words or phrases in the names of people or groups responsible for creating or collecting a work:

• Personal authors and creators, including individuals and families who serve as editors, performers, photographers, artists, etc.
• Non-personal authors and creators, including corporations, government bodies, conferences, jurisdictions, projects, events, and entities like ships and musical groups.

Enter one or more parts of the name in any order. Results will be displayed as a Titles List, sorted by relevance. Entering more parts of the name should make your search more precise (each result will contain ALL of the words you enter).

Note that if you are looking for materials about an author or creator (real or fictional), search by Keyword (SUBJECT).

Keyword (SUBJECT)

Finds all words or phrases in subject areas of the record. Subjects include topical subjects, geographical place names, occupations, and genres/forms of material. Subjects are selected from controlled lists of words or phrases used by the Library of Congress.

Keyword (ALL) Quick Search

A Keyword (ALL) Quick Search box, located at the top of every LC Catalog page, finds all words in any order or exact phrases located anywhere in catalog records.

Relevancy Ranking

Keyword Search results are displayed as a Titles List in ranked order using a special relevancy algorithm. Relevancy ranking is commonly used for most web searches, but web search engines rely on different formulas to determine relevancy. The LC Catalog uses the following ranking factors:

• Uniqueness of search terms within the LC Catalog
• Proximity of search terms to each other within the LC Catalog record
• Number of times a search word is present in LC Catalog record fields (e.g., in a subject heading field, author field, title field)

Punctuation, Diacritics, Special Characters, Non-Latin Characters

Most marks of punctuation in your search query are converted to spaces. Most diacritics and some punctuation marks are removed (including apostrophes, alifs, ayns, middle dots, primes and double primes). A few special characters, however, are retained in searches: ampersands (&), plus signs (+), at signs (@), number signs (#), and musical flat (♭) and natural (♮) signs (musical sharps are converted to spaces). Special characters are generally converted to their nearest alphabetic equivalent (for example: an æ diagraph to ae or a þ thorn to th).

Records in the LC Catalog use Unicode opens in a new window (UTF-8 encoding) for searching and displaying data. In addition to Latin scripts, the catalog contains records in the following languages/scripts: Chinese, Japanese, Korean; Cyrillic-based scripts; Greek; Hebrew, Yiddish; and Perso-Arabic script (e.g., Arabic, Persian, Pushto, Sindhi, Urdu). For more information, see Searching/Displaying Non-Latin Characters.

In general, your preferred web browser settings will not need to be changed to correctly view records that contain diacritics, special characters, or non-Latin characters. If you have problems, however, you may need to reconfigure your browser opens in a new window. Best results occur if you have Unicode fonts and use Unicode character encoding with automatic character encoding activated.

Adding Limits

To filter your search, toggle open Add Limits and select:

• Year Published/Created of the material
• Language of the material
• Type of material (e.g., book, periodical, music score)
• Location of the collection within the Library of Congress
• Place of Publication (e.g., country, state, province)

Searches in the LC Catalog can return thousands of results. Search limits can be useful to refine your results, but should be used with caution. Many older records do not contain the data that is used to set limits, and so these records will not appear in search results. Similarly, some formats of material (such a images) may not contain data such as language information; limiting by language will exclude these records from your results. In addition, when multiple values (e.g., several languages) are encoded in a single field of a catalog record, limits can only retrieve the first language. If relevant material is not retrieved with limits set, clear the limits and modify the search.

Search Tips for Keyword (ALL, TITLE, AUTHOR/CREATOR, SUBJECT)

• Enter words or phrases in any order. Search results will match all words (including articles and conjunctions in all languages, such as: and, or, not, the, a, la, das, al-, etc.).
• Search results are ranked using a relevancy algorithm. To improve the relevancy of your results, try including more words or phrases in your search.
• Try quotation marks (" ") when searching words you want treated as a phrase (e.g., "tax reform"). These four Keyword Search options find phrases across subfields.
• Use a percent sign (%) as a single character wildcard, either inside or at the end of a search term (e.g., col%r retrieves color, coler, and colur, but not colour). If your search terms contain a percent sign, remove the %. For example, to find the title: 100% solution enter 100 solution.
• Use a question mark (?) for truncation (different forms of a root word) and as a multiple character wildcard, either inside or at the end of a search term (e.g., ecumen? retrieves ecumenical and ecumenism). Truncated search terms must be two or more characters long (e.g., KF? not K?).
• Most punctuation marks (hyphens, slashes, periods, etc.) are replaced by spaces. Because spaces are used to divide words, use quotation marks to treat your search term as a phrase when punctuation occurs in the middle of your term (e.g., "U.S.A." or "part-time"). Keyword number searches are especially tricky. Treat punctuation in numbers as word separators and enclose numbers with punctuation in quotation marks in your search query.
• Capitalization does not matter.
• Add limits to filter your search.
• Select the number of items you want to display in your search results Titles List. You can increase the default of 25 results to 50, 75, or 100.
• Search results return up to 10,000 entries for each query.

Keyword (EXPERT)

Keyword (EXPERT) offers a powerful, command-driven search method for finding words or phrases located anywhere in the record. Expert search allows for greater precision by supporting Boolean operators, user-specified nesting, and special index codes. Expert searches also allow more complex combination of multiple terms from one or more fields in a record. Boolean operators (AND, OR, NOT) may be used with or without parentheses. Many number searches can be entered as either keyword searches (where parts of a number may cross subfields and punctuation marks are treated as word separators) or as left-match searches (where punctuation and subfielding are taken into account).

Search Tips for Keyword (EXPERT)

• Combine several terms using the Boolean operators AND, OR, or NOT (entered in upper or lower case).
  • AND - narrows your search by combining multiple concepts (e.g., mars AND mission)
  • OR - broadens your search with related terms for each concept (e.g., ten OR 10)
  • NOT - excludes terms from your search (e.g., marketing NOT sales)
    Note: use caution when selecting the Boolean NOT operator so you do not inadvertently exclude desired records (e.g., NOT Mexico will remove records containing both Mexico and New Mexico).
  • If you want to include the words AND, OR, or NOT as search words, you must include them, along with other words, in quotes as a phrase.
• Combine several Boolean operators in a single search statement, using parentheses to group concepts together. For example: (wood? OR forest) AND "resource manage?"
• Restrict search words or phrases to a particular index (or area of the record), by first specifying the appropriate index code followed by your search word or phrase (e.g., ktil five AND kpnc lewis).
• Use quotation marks around queries that contain multiple search terms (for example: KNAM "washington george" and KSUB diaries).
• Search terms, including quoted phrases, are not searched across subfields. Instead index codes/search terms need to be combined using Boolean operators (e.g., KCLA "E169.1" and KCLA "N3745 1975").
• Boolean OR expressions are executed first, followed by expressions using AND or NOT (which are considered equivalent). Processing of equivalent expressions takes place in a left-to-right sequence.
• Use a percent sign (%) as a single character wildcard, either inside or at the end of a search term (e.g., col%r retrieves color, coler, and colur, but not colour). If your search terms contain a percent sign, remove the %. For example, to find the title: 100% solution enter 100 solution.
• Use a question mark (?) for truncation (different forms of a root word) and as a multiple character wildcard, either inside or at the end of a search term (e.g., ecumen? retrieves ecumenical and ecumenism). Truncated search terms must be two or more characters long (e.g., KF? not K?).
• You can use both keyword and left-match index codes in Keyword (EXPERT) searches. Note, however, that while multiple keyword index codes can be combined using Boolean operators, only a single left-match index code can be used in each search. In addition, truncation in Keyword (EXPERT) left-match queries is not automatic.
• Add limits to filter your keyword and left-match searches.