Perhaps you should try some spelling variations:
"supply scale irrigation schemes." » "supply scale irrigation scheme.", "supply scale irrigation systems.", "supply case irrigation schemes.", "supply scheme irrigation schemes.", "supply social irrigation schemes."
"supply about integration theory." » "supply about integration through.", "supply about information theory.", "supply about innovation theory.", "supply youth integration theory.", "supply about international theory.", "supply without integration theory.", "supply cost integration theory.", "supply south integration theory.", "supply asset integration theory."

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

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