5. The computer-implemented method of claim 4 , wherein the information includes evidence as to whether a phrase in the multi-term search query and a phrase in the altered query are synonymous.
4. The computer-implemented method of claim 1 , wherein selecting a replacement term comprises: identifying multi-term query pairs in stored data; analyzing information corresponding to the multi-term query pairs; selecting a subset of the multi-term query pairs for which the second queries of the multi-term query pairs include candidate replacement terms for a phrase in the first queries of the multi-term query pairs; and ranking the candidate replacement terms.