Perhaps you should try some spelling variations:
biography pericles » biography problems, biography periodicals
biography sermons » biography germany, biographical sermons
rand corporation » said corporation, road corporation, a corporation
biography series » biography sources, biography studies, biography herve

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: rand corporation ((((biography series) OR (biography pericles))) OR (biography sermons)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "rand corporation ((((biography series) OR (biography pericles))) or (biography sermons))".
• Adding a wildcard symbol may retrieve word variants: rand corporation ((((biography series) OR (biography pericles))) or (biography sermons))*.