Perhaps you should try some spelling variations:
"supply data irrigation schemes." » "supply data irrigation scheme.", "supply data irrigation systems.", "supply canal irrigation schemes.", "supply water irrigation schemes.", "supply spate irrigation schemes."
"supply change irrigation system." » "supply change mitigation system.", "supply canal irrigation system.", "supply large irrigation system.", "supply change irrigation systems.", "supply change irrigation water.", "supply change irrigation scheme.", "supply charges irrigation system.", "supply chain irrigation system.", "supply chains 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 change irrigation system.") or ("supply data irrigation schemes."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply change irrigation system.") OR ("supply data irrigation schemes."))*.
• Removing quotes may allow a broader search: (( supply change irrigation system. ) or ( supply data irrigation schemes. ))*.