1. A context-driven search method comprising: having a user provide an input phrase that is used to search a collection of language-based information sources, wherein a phrase is one or more words or other language-based character strings; identifying sets of substantially-equivalent expanded phrases that are relevant to the input phrase, wherein these expanded phrases appear in the collection of language-based information sources, wherein an expanded phrase relevant to an input phrase is defined as a phrase that includes the input phrase, or a minor variation thereof, plus one or more additional phrases; and wherein this minor variation is defined as a variation selected from one or more of the variations in the group consisting of: a phrase with words that are corrected or alternative spelling variations of the words comprising the input phrase; a phrase with words that are grammatical variations (such as variation in tense, plurality, or voice) of the words comprising the input phrase; a phrase with words that are the same as those comprising the input phrase, except for the addition or deletion of grammatical articles (such as “a” or “an” or “the”) or relatively-neutral modifiers (such as “very” or “especially”); a phrase with words that are the same as those comprising the input phrase, but are in a different word order; a phrase with words that are the same as those comprising the input phrase, except for case variation (such as upper vs. lower case) in one or more letters in the input phrase; a phrase with the same words as those comprising the input phrase, but with variation in punctuation or word contraction; a phrase that is a phrase synonym for the input phrase, wherein a phrase synonym is defined as alternative phrase that can be substituted for an original phrase in the collection of language-based information sources without substantively changing meaning or creating a grammatical error in the language-based information sources; and a phrase that has been found to be highly-associated with the input phrase based on analysis of previous search patterns; and providing the user with set-specific summary information concerning some, or all, of these sets of substantially-equivalent expanded phrases.