7. A computing device comprising: a memory; one or more processors operatively coupled to the memory; a session segmentation module maintained in the memory and executed on the one or more processors configured to segment search session logs of a user into search sessions and to identify a first keyword set and a second keyword set from a search session; and a similarity calculation module maintained in the memory and executed on the one or more processors configured to: determine a minimum frequency as a smaller of a frequency at which the first keyword set occurs and a frequency at which the second keyword set occurs; combine the first keyword set and the second keyword set to form a keyword set pair; calculate a similarity value for the first and second keyword sets based at least in part on a comparison made between the minimum frequency and a frequency at which the keyword set pair occurs in the search session; compare the similarity value with a similarity threshold; and display one or more semantically relevant keyword sets based on the comparison; and a threshold calculation module maintained in the memory and executed on the one or more processors configured to: generate a training set which includes a predetermined number of queries obtained from one or more training search sessions; identify a predetermined number of suggested queries for each query in the training set based on a relevance of the suggested queries to each query in the training set; categorize the suggested queries into one or more groups based on the relevance; determine a level of relevance for each of the one or more groups based on the relevance of the suggested queries categorized into each of the one or more groups; and determine the similarity threshold based in part on the level of relevance of at least one of the one or more groups.
8. The computing device of claim 7 , wherein the similarity value is determined based on one or more of a total number of query sessions, a first number of queries including the first keyword set, a second number of queries including the second keyword set and a third number of queries including the keyword set pair.