One of the uses of this syntax is to search for more than two words or phrases. For example, suppose you wanted to find all documents that pertained to either "maple" or "cherry" but which also pertained to "pruning". Using parentheses to compose the above-mentioned search, you would enter:
(maple | cherry) & pruning
In the search criteria specified above, the pipe "|" represents "OR" and the ampersand "&" represents "AND."
Proximity searches are performed by entering a carat (^) followed by the maximum number of words separating the two phrases. Thus, if you were only interested in documents where "pruning" was within 15 words of either "maple" or "cherry", you would enter:
(maple | cherry) ^15 pruning