Perhaps you should try some spelling variations:
"physical chemical" » "physico chemical"
"physical chemist" » "physician chemist", "physical schemas", "biophysical chemists"
"physical chemistry" » "physician chemistry", "physical schemasry", "biophysical chemistsry"

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: (((("physical chemist") OR ("physical chemical"))) OR ("physical chemistry")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"physical chemist\") OR (\"physical chemical\"))) or (\"physical chemistry\"))".
• Removing quotes may allow a broader search: (((( physical chemist ) OR ( physical chemical ))) or ( physical chemistry )).
• Adding a wildcard symbol may retrieve word variants: (((("physical chemist") OR ("physical chemical"))) or ("physical chemistry"))*.