Perhaps you should try some spelling variations:
medical scientists » biomedical scientists, american scientists, physical scientists
robert wrench » robert french, roberto french, robert weech
robert watson » robert nelson, robert warren
robert welch » robert weech, robert wells, robert kelchen

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: ((((robert welch) OR (robert wrench))) OR (robert watson)) (medical scientists).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((robert welch) OR (robert wrench))) or (robert watson)) (medical scientists)".
• Adding a wildcard symbol may retrieve word variants: ((((robert welch) OR (robert wrench))) or (robert watson)) (medical scientists)*.