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 design irrigation system." » "supply basin irrigation system.", "supply deficit irrigation system.", "supply drip irrigation system.", "supply design irrigation systems.", "supply design irrigation water.", "supply design irrigation scheme.", "supplies design irrigation system.", "support design irrigation system.", "supply decisions irrigation system."

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 design irrigation system."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply trade integration theories.") OR ("supply design irrigation system.")).
• Removing quotes may allow a broader search: (( supply trade integration theories. ) or ( supply design irrigation system. )).
• Adding a wildcard symbol may retrieve word variants: (("supply trade integration theories.") or ("supply design irrigation system."))*.