Perhaps you should try some spelling variations:
research professor » research profession, research progresson, research processes
research problems » research project, research program
research projects » research project
research progress » research program, research project
research process » research project, research program, research papers

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 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 projects ))) or ( research progress ))))))".
• Adding a wildcard symbol may retrieve word variants: (( research professor ) or ((( research process ) or ((((( research problems ) OR ( research projects ))) or ( research progress ))))))*.