+

A leading plus sign indicates that this word must be present in each page that is returned.

-

A leading minus sign indicates that this word must not be present in any of the pages that are returned.

(no operator)

By default (when neither + nor - is specified) the word is optional, but the pages that contain it are rated higher.

> <

These two operators are used to change a word's contribution to the relevance value that is assigned to a page. The > operator increases the contribution and the < operator decreases it. See the example below.

( )

Parentheses are used to group words into subexpressions. Parenthesized groups can be nested.

~

A leading tilde acts as a negation operator, causing the word's contribution to the page's relevance to be negative. This is useful for marking “noise” words. A page containing such a word is rated lower than others, but is not excluded altogether, as it would be with the - operator.

*

The asterisk serves as the truncation operator. Unlike the other operators, it should be appended to the word to be affected.

"

A phrase that is enclosed within double quote (‘"’) characters matches only pages that contain the phrase literally, as it was typed. The engine then performs a substring search for the phrase in the records that are found, so the match must include non-word characters in the phrase. For example, "test phrase" does not match "test, phrase".

If the phrase contains no words that are in the index, the result is empty. For example, if all words are either stopwords or shorter than the minimum length of indexed words, the result is empty.

'apple banana'

Find pages that contain at least one of the two words.

'+apple +juice'

Find pages that contain both words.

'+apple macintosh'

Find pages that contain the word “apple”, but rank pages higher if they also contain “macintosh”.

'+apple -macintosh'

Find pages that contain the word “apple” but not “macintosh”.

'+apple +(>turnover <strudel)'

Find pages that contain the words “apple” and “turnover”, or “apple” and “strudel” (in any order), but rank “apple turnover” higher than “apple strudel”.

'apple*'

Find pages that contain words such as “apple”, “apples”, “applesauce”, or “applet”.

'"some words'

Find pages that contain the exact phrase “some words” (for example, pages that contain “some words of wisdom” but not “some noise words”). Note that the ‘"’ characters that surround the phrase are operator characters that delimit the phrase. They are not the quotes that surround the search string itself.