18. The system of claim 11 , wherein the instructions cause the one or more processors to perform actions comprising selecting a replacement token for the particular search token from the set of related tokens.
11. A system comprising: one or more data stores storing a query log that includes search queries for a plurality of different search sessions; and data processing apparatus including one or more processors that execute instructions that cause the one or more processors to interact with the data store and to perform actions including: receiving a first set of search queries during a first search session; identifying, from the first set of search queries, a first set of search tokens; identifying, from the query log, a second search session during which at least a threshold portion of the first set of search tokens were included in a second set of search queries received during the second search session; selecting, as related tokens for the first search session, a second set of search tokens from the second set of search queries; receiving a current search query during the first search session; determining, based on the query log, that the current search query has historically been revised by users to replace a particular search token from the first set of search tokens with one of the related tokens; and creating a suggested search query in which the particular search token is replaced by the one of the related tokens.