Perhaps you should try some spelling variations:
"supply cost irrigation schemes." » "supply cost irrigation systems.", "supply cost irrigation systemss.", "supply crop irrigation schemes.", "supply cost mitigation schemes.", "supply lift irrigation schemes.", "supply costs irrigation schemes."
"supply change irrigation scheme." » "supply change mitigation scheme.", "supply canal irrigation scheme.", "supply large irrigation scheme.", "supply change irrigation systems.", "supply charges irrigation scheme.", "supply chain irrigation scheme.", "supply chains irrigation scheme."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("supply change irrigation scheme.") or ("supply cost irrigation schemes."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply change irrigation scheme.") OR ("supply cost irrigation schemes."))*.
• Removing quotes may allow a broader search: (( supply change irrigation scheme. ) or ( supply cost irrigation schemes. ))*.