After the initial keyword query, the rank-ordered list of documents, terms, or both that best matches your query will be displayed. Each item is preceded by a checkbox. By selecting the checkbox next to an item, that item is automatically used as part of the next query.
Using documents as part of the query (called relevance feedback) takes advantage of the fact that it is often easier to recognize relevant documents than it is to describe your interests by means of keywords. By selecting a document, you are instructing LSI to find other similar documents.
Selecting the checkbox next to a term adds that term to the query, as if you had entered it manually in the "Keyword Query" box.
When the query is resubmited and the subsequent results returned, documents and terms that were added to the previous query by selecting their checkboxes are marked with a "Q" next to their score.