14. A system comprising: a memory; a processor coupled to the memory; a graph module stored in the memory and executable on the processor to; construct a graph from mobile search logs to identify queries from mobile search logs; identify, for each of the queries, a user that sent a query, a time at which the user sent the query, and a location from which the user sent the query, the graph representing: each of the users and the query sent by the user as two nodes; and the time at which the user sent the query and the location from which the user sent the query as an edge; and calculate distances between the current time and the current location and the times and the locations with the edges between the two nodes; a similarity module stored in the memory and executable on the processor to compute a similarity between the users from the graph based at least in part on similarities between: (1) the queries, (2) the times at which the users submitted the queries, and (3) the locations from which the users submitted the queries; and a time-location awareness application module stored in the memory and executable on the processor to receive, from a mobile computing device of a particular user, a query input associated with a current time and a current location of the mobile computing device.
14. A system comprising: a memory; a processor coupled to the memory; a graph module stored in the memory and executable on the processor to; construct a graph from mobile search logs to identify queries from mobile search logs; identify, for each of the queries, a user that sent a query, a time at which the user sent the query, and a location from which the user sent the query, the graph representing: each of the users and the query sent by the user as two nodes; and the time at which the user sent the query and the location from which the user sent the query as an edge; and calculate distances between the current time and the current location and the times and the locations with the edges between the two nodes; a similarity module stored in the memory and executable on the processor to compute a similarity between the users from the graph based at least in part on similarities between: (1) the queries, (2) the times at which the users submitted the queries, and (3) the locations from which the users submitted the queries; and a time-location awareness application module stored in the memory and executable on the processor to receive, from a mobile computing device of a particular user, a query input associated with a current time and a current location of the mobile computing device. 15. The system of claim 14 , further comprising: a relatedness module stored in the memory and executable on the processor to compute a relatedness of each of multiple candidate queries to the query input based at least in part on the calculated similarity between the users, calculating a difference between the current time associated with the received query input and a time when the candidate query was submitted, and calculating a distance between the current location associated with the received query input and a location where the candidate query was submitted.