Perhaps you should try some spelling variations:
"research professor" » "research profession", "research process", "research processes"
"research progress" » "research project"
"research projects" » "research project"
"research problems" » "research project"
"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 progress") OR ("research projects"))) OR ((("research problems") OR ("research program")))))).
• Removing quotes may allow a broader search: (( research professor ) or ((((( research progress ) or ( research projects ))) or ((( research problems ) or ( research program )))))).
• Adding a wildcard symbol may retrieve word variants: (("research professor") or ((((("research progress") or ("research projects"))) or ((("research problems") or ("research program"))))))*.