Perhaps you should try some spelling variations:
physical scientists » political scientists, physical sciences, physical societies
medical scientists » biomedical scientists, american scientists, medical sciences
robert walsh » robert walser, robert walt, robert welch
robert watt » robert watson, robert white

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