2. The method of claim 1 , further comprising: receiving a subsequent search query after receiving the additional search query; associating the subsequent search query with the current search session to form an updated current search session; and identifying, from the similar subset of previous search sessions and as similar previous search sessions, one or more individual previous search sessions that are similar to the updated current search session, wherein each identified similar previous search session is identified as being similar to the updated current search session based on at least a subset of search queries of the updated current search session matching a subset of search queries of the identified similar previous search session.
1. A method comprising: receiving, by one or more computers and from a user device, a first search query during a current search session, the first search query comprising one or more first query terms; receiving, by one or more computers and from the user device, an additional search query during the current search session, the additional search query comprising one or more additional query terms and the additional search query being received subsequent to search results for the first search query being provided in response to the first search query; identifying, by one or more computers and from a set of previous search sessions that each concluded prior to the current search session, a similar subset of previous search sessions, each individual previous search session of the similar subset being identified for inclusion in the similar subset based on the individual previous search session being a search session during which the first search query and the additional search query were both received, the similar subset lacking at least one previous search session of the set of previous search sessions; identifying, by one or more computers and from the similar subset of previous search sessions, a set of follow-up search queries, each follow-up search query being a search query that was received subsequent to receipt of the first search query and the additional search query in at least one of the previous search sessions of the similar subset; identifying, by one or more computers and for each follow-up search query, a frequency at which the follow-up search query was received in previous search sessions subsequent to receipt of the first search query and the additional search query; aggregating the set of follow-up search queries from the similar subset of previous search sessions; selecting from the aggregated follow-up search queries and based on the identified frequencies having the highest frequency of occurrence, a suggested search query for presentation in response to receipt of the additional search query during the current search session; and providing the suggested search query with search results for the additional search query.