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