Systems and method for enhancing search functionality provided to a user. In certain aspects, a query processing engine automatically decomposes queries into constituent units that are related to concepts in which a user may be interested. The query processing engine decomposes queries into one or more constituent units per query using statistical methods. In certain aspects, no real world knowledge is used in determining units. In other aspects, aspects of world and content knowledge are introduced to enhance and optimize performance, for example, manually using a team of one or more information engineers.