Perhaps you should try some spelling variations:
integration theories » integration theory, integration through, integration efforts
cooperation efforts » conservation efforts, collection efforts, conservation effort
social integration » global integration, financial integration, regional integration
trade cooperation » border cooperation, trade creation
supply trade » supply side, 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: (( supply trade cooperation efforts. ) or ( supply social integration theories. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( supply trade cooperation efforts. ) OR ( supply social integration theories. )).
• Adding a wildcard symbol may retrieve word variants: (( supply trade cooperation efforts. ) or ( supply social integration theories. ))*.