Perhaps you should try some spelling variations:
"supply social integration theories." » "supply social integration theorems.", "supply social integrationstheorie 2.", "supply social integration theory.", "supply global integration theories.", "supply financial integration theories.", "supply regional integration theories."
"support through irrigation schemes." » "support through variation schemes.", "support through integration schemes.", "support through arbitration schemes.", "support through irrigation scheme.", "support through irrigation systems."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("support through irrigation schemes.") or ("supply social integration theories."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("support through irrigation schemes.") OR ("supply social integration theories.")).
• Removing quotes may allow a broader search: (( support through irrigation schemes. ) or ( supply social integration theories. )).
• Adding a wildcard symbol may retrieve word variants: (("support through irrigation schemes.") or ("supply social integration theories."))*.