4. The method according to claim 1 , wherein: the execution of each of the sub-queries includes identifying a multitude of search results for at least one of the sub-queries; and each of said clusters represents a high level entity.
4. The method according to claim 1 , wherein: the execution of each of the sub-queries includes identifying a multitude of search results for at least one of the sub-queries; and each of said clusters represents a high level entity. 5. The method according to claim 4 , wherein: the combining includes determining the relevance score for each of the clusters based on relevance scores of the search results which form the cluster.