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