1. A method of searching documents, comprising: indexing a plurality of documents into a document library stored in a database; receiving a query document; comparing, using a processor, the query document with each indexed document to generate a score for each indexed document, the score representing a measure of similarity between the query document and each indexed document; determining a commonality among particular ones of the indexed documents, other than the measure of similarity; displaying, at a user interface, a query result based on the score for each indexed document and based on the commonality; calculating hash values for each indexed document over each of a plurality of alternative windows; storing the hash values for each indexed document over each of the plurality of alternative windows; receiving user input selecting a particular one of the plurality of alternative windows; in response to receiving the selection of the particular one of the plurality of alternative windows, calculating hash values for the query document using the particular one of the plurality of alternative windows; and comparing the hash values for the query document with the hash values corresponding to the particular one of the plurality of alternative windows for each of the indexed documents to determine a measure of similarity between the query document and each indexed document.