To find matches when your search terms are near one another, put your words in quotes and follow with a tilde ~ and a number indicating how far apart the matching words can be. This technique is known as a proximity search. For example, to find the words john and booth within a span of four words, "john booth"~4.

Alternate words

To match any of the words you've entered, enter OR between words. For example, antietam OR sharpsburg. The symbol || can be used in place of the operator OR.

Exclude words

To eliminate matches on a word, precede the word with NOT. For example, "civil war" NOT spanish. The symbols "-" or "!" can be used in place of the operator NOT.

Word variations

Wildcard characters can help find different forms of a word. Use "*" to represent any number of characters; for example, archiv* matches archive, archives, archiving, archival, etc. Use "?" to represent one additional character, for example, archive? matches archive and archives.

Increasing the relevance of a search term

If your search includes more than one word, and you'd like matches for one of the words to be given more importance, follow the term with the caret "^" and a number greater than 1. For example, to change the relevance ranking when searching the words lincoln gettysburg to highlight results that emphasize Abraham Lincoln's role, try lincoln^4 gettysburg.

Sophisticated searches

The logic of a search can be controlled with parentheses. For example,
(antietam OR sharpsburg) AND maryland matches descriptions that include the word maryland with either the word antietam or sharpsburg.

Results

When you get your search results, the most relevant matches appear first. Relevance is determined by several factors, including the number of times the search terms appear in the description, the length of the field where matches occur, the number of words in the search, and any emphasis given to one or more of the search terms or one or more of the fields.

Some terms may have different meanings in different contexts: For example, columbia may return results that are not as relevant from the searcher's point of view. Adding different words—in this case, "columbia space shuttle" or "columbia university"—can help.

The index for searching collection descriptions uses the Lucene text search engine library.