Perhaps you should try some spelling variations:
"research problemses" » "research problems", "research problem", "research progresses"
"research professor" » "research profession", "search processor", "research professional"
"research processes" » "research procedures", "research projects", "research progress", "research progresses", "research projectses", "research problemses"
"research prozess" » "research progress", "research propels", "research proteases"
"research process" » "research progress", "research projects", "research problems"

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