Perhaps you should try some spelling variations:
peter murray » protter murray, petrie murray
peter gray » peter ray, peter grant, peter graham
peter bray » peter brady, peter ray, peter brian
peter graf » peter grant

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: ((((((peter gray) OR (peter murray))) OR (peter bray))) OR (peter graf)) (bioengineer).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((peter gray) OR (peter murray))) or (peter bray))) or (peter graf)) (bioengineer)".
• Adding a wildcard symbol may retrieve word variants: ((((((peter gray) OR (peter murray))) or (peter bray))) or (peter graf)) (bioengineer)*.