18. The computer system of claim 15 wherein the component that identifies a phrase selects words with top scores, locates each selected word within the documents as a part of a phrase, and extends each phrase by words proximate to the phrase based at least in part on the first score of each of the words proximate to the phrase.
19. The computer system of claim 18 wherein a phrase is only extended by words having an associated first score indicating relatedness to the item.