1. A system for retrieval of text comprising: a processor comprising: instructions for searching an associated storage medium in response to a user query and for retrieving text strings from responsive documents, the retrieved text strings comprising sentences; instructions for displaying the text strings of the responsive documents; instructions for thereafter receiving a user's selection of text fragments from a user-selected one of the displayed sentences; instructions for identifying grammar rules associated with the user-selected text fragments of the user-selected one of the displayed text strings, and instructions for generating a new query and for retrieving additional text strings from the associated storage medium which satisfy the identified grammar rules; a display for displaying retrieved text strings; and a user input device in communication with the processor which enables a user to select text fragments of a same displayed text string for generating the new query, the processor identifying grammar rules associated with the user-selected text fragments and retrieving text strings from the storage medium which satisfy the grammar rules.