You can enter multiple words separated by spaces: "bypass switch". Then select the query type, the number of results to display per page and the source of documents to search.

You can expand your seach by using "Wildcard" symbols. For example: entering the word "All" will find documents containing the word "all" but not "allegorical." You can use wildcards, however to broaden the scope of the search. "All*" will return documents containing both "all" and "alliterate." Case is ignored.