Perhaps you should try some spelling variations:
"research profession" » "research professional", "research progression", "research professionals"
"research professor" » "research progresson", "search processor", "research professional"
"research processes" » "research procedures", "research projects", "research progress", "research progresses", "research projectses", "research projectes"
"research problems" » "research progress", "research project", "research program"
"research prozess" » "research progress", "research propels", "research proteases"
"research process" » "research progress", "research projects", "research project"

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: (((((("research professor") OR ("research profession"))) OR ((("research prozess") OR ((("research process") OR ("research problems"))))))) OR ("research processes")).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((((\"research professor\") or (\"research profession\"))) or (((\"research prozess\") or (((\"research process\") OR (\"research problems\"))))))) or (\"research processes\"))".
• Removing quotes may allow a broader search: (((((( research professor ) or ( research profession ))) or ((( research prozess ) or ((( research process ) OR ( research problems ))))))) or ( research processes )).
• Adding a wildcard symbol may retrieve word variants: (((((("research professor") or ("research profession"))) or ((("research prozess") or ((("research process") OR ("research problems"))))))) or ("research processes"))*.