Perhaps you should try some spelling variations:
research professor » research profession, research process, search processor
research processes » research process, research procedures, research progress
research projects » research project
research prozess » research process, research progress, research propels

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 processes) OR (research projects)) ))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(((( research professor ) or ( research prozess ))) or ( ((research processes) OR (research projects)) ))*".