Perhaps you should try some spelling variations:
"supply trade integration theories." » "supply trade integration theorems.", "supply trade integrationstheorie 2.", "supply trade integration theory.", "supply case integration theories."
"supply gaps integrating surveys." » "supply gaps integrated surveys.", "supply gaps integrating europe's.", "supply gaps integrating services.", "supply _ integrating surveys.", "supply 4 integrating surveys.", "supply 6 integrating surveys.", "supply gap integrating surveys.", "supply gas integrating surveys."

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 integration theories.") or ("supply gaps integrating surveys."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply trade integration theories.") OR ("supply gaps integrating surveys."))*.
• Removing quotes may allow a broader search: (( supply trade integration theories. ) or ( supply gaps integrating surveys. ))*.