Perhaps you should try some spelling variations:
integration efforts » international efforts, conservation efforts
population reforms » population before, population norms, education reforms
school population » school education, school completion, school location
survey school » survey tool, sydney school
supply trade » supply case

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( survey school population reforms. ) or ( supply trade integration efforts. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( survey school population reforms. ) OR ( supply trade integration efforts. )).
• Adding a wildcard symbol may retrieve word variants: (( survey school population reforms. ) or ( supply trade integration efforts. ))*.