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