1. A computer-implemented method facilitating a search, comprising: under control of one or more computer systems configured with executable instructions, clustering search terms extracted from previous searches into a plurality of search term clusters independent of human supervision; identifying at least one search phrase comprising at least two search terms from a distinguished cluster of the plurality of search term clusters as statistically significant with respect to search phrases of the distinguished cluster; determining at least one relevance score for said at least one search phrase with respect to a collection of content; and providing at least one result of the search for presentation, said at least one result at least referencing content selected from the collection of content based at least in part on said at least one relevance score.