Perhaps you should try some spelling variations:
"supply case irrigation schemes." » "supply case irrigation scheme.", "supply case irrigation systems.", "supply scale irrigation schemes.", "supply use irrigation schemes.", "supply change irrigation schemes.", "supply cost irrigation schemes.", "supply chain irrigation schemes.", "supply curve irrigation schemes."
"supply situ conservation efforts." » "supply bird conservation efforts.", "supply nature conservation efforts.", "supply land conservation efforts.", "supply side conservation efforts.", "supply shifts conservation efforts.", "supply sides conservation efforts."

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

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