Perhaps you should try some spelling variations:
"supply delta irrigation schemes." » "supply delta irrigation scheme.", "supply delta irrigation systems.", "supply et irrigation schemes.", "supply alfa irrigation schemes.", "supply mega irrigation schemes.", "supply data irrigation schemes.", "supply adults irrigation schemes."
"supply good conservation efforts." » "supply wood conservation efforts.", "supply good conversation efforts.", "supply good conversations efforts.", "supply food conservation efforts.", "supply cold conservation efforts.", "supply crowd 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 good conservation efforts.") or ("supply delta irrigation schemes."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply good conservation efforts.") OR ("supply delta irrigation schemes.")).
• Removing quotes may allow a broader search: (( supply good conservation efforts. ) or ( supply delta irrigation schemes. )).
• Adding a wildcard symbol may retrieve word variants: (("supply good conservation efforts.") or ("supply delta irrigation schemes."))*.