Perhaps you should try some spelling variations:
"supply basin irrigation schemes." » "supply basin irrigation scheme.", "supply basin irrigation systems.", "supply drip irrigation schemes.", "supply canal irrigation schemes.", "supply farm irrigation schemes.", "supply chain irrigation schemes.", "supply case irrigation schemes."
"supply situ conservation efforts." » "supply soil conservation efforts.", "supply bird conservation efforts.", "supply nature conservation efforts.", "supply side conservation efforts.", "supply sides conservation efforts."

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply basin irrigation schemes.") OR ("supply situ conservation efforts."))~.
• Removing quotes may allow a broader search: (( supply basin irrigation schemes. ) or ( supply situ conservation efforts. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply basin irrigation schemes.") or ("supply situ conservation efforts."))*.