Perhaps you should try some spelling variations:
"support can irrigation schemes." » "support can irrigation scheme.", "support can irrigation systems.", "support canal irrigation schemes.", "support tank irrigation schemes.", "support change irrigation schemes.", "support chuan irrigation schemes.", "support bank irrigation schemes.", "support a irrigation schemes."
"support state interaction terms." » "support state interactions terms.", "support scale interaction terms.", "support state intervention terms.", "support state interaction term.", "support stage interaction terms.", "support staff interaction terms.", "support start interaction terms."

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

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