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 grid conservation efforts." » "supply aid conservation efforts.", "supply good conservation efforts.", "supply grass conservation efforts.", "supply crowd conservation efforts.", "supply great conservation efforts.", "support grid 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 case irrigation schemes.") OR ("supply grid conservation efforts."))~.
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