Perhaps you should try some spelling variations:
"research professor" » "research profession", "research processes", "research prozess"
"research problems" » "research projects"
"research progress" » "research projects"
"research process" » "research projects", "research papers", "research proceedings"

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