1. A computer-implemented method, comprising: defining query extraction criteria, the query extraction criteria configured to identify queries related to a subject relevance; identifying a candidate query from the queries stored in a query log according to the extraction criteria; generating relevancy scores for a first set of web documents, each relevancy score associated with a corresponding web document in the first set of web documents and being a measure of the relevance of the candidate query to the web document; selecting web documents having an associated relevancy score that exceeds a relevancy threshold; and generating a query-page candidate tuple from the selected web documents and the candidate query.