7. A network device for searching data, comprising: memory having data and instructions; and a processor to execute the data and instructions to perform actions, including: receiving, from a client device, one or more search terms; determining at least one concept based on an analysis of the one or more search terms; identifying one or more concept-specific data sources over which to perform searches based on the at least one concept; performing a search over each of the one or more concept-specific data sources based at least on the search term to generate a plurality of clusters, search results from each concept-specific data source comprising a different cluster in the plurality of clusters; determining a relevance score for each result within each cluster based on user specific contextual data for a user of the client device; for each cluster in the plurality of clusters, employing at least the relevance scores of each result within the respective cluster to determine a respective cluster score; generating an ordered listing of each of the plurality of clusters based on the respective cluster scores; and displaying at the client device at least a portion of the ordered plurality of clusters.
7. A network device for searching data, comprising: memory having data and instructions; and a processor to execute the data and instructions to perform actions, including: receiving, from a client device, one or more search terms; determining at least one concept based on an analysis of the one or more search terms; identifying one or more concept-specific data sources over which to perform searches based on the at least one concept; performing a search over each of the one or more concept-specific data sources based at least on the search term to generate a plurality of clusters, search results from each concept-specific data source comprising a different cluster in the plurality of clusters; determining a relevance score for each result within each cluster based on user specific contextual data for a user of the client device; for each cluster in the plurality of clusters, employing at least the relevance scores of each result within the respective cluster to determine a respective cluster score; generating an ordered listing of each of the plurality of clusters based on the respective cluster scores; and displaying at the client device at least a portion of the ordered plurality of clusters. 11. The network device of claim 7 , wherein determining a relevance score further comprises employing weighting factors to determine the relevance score that employs a user behavior information.