Perhaps you should try some spelling variations:
"supply change irrigation schemes." » "supply change irrigation scheme.", "supply change mitigation schemes.", "supply canal irrigation schemes.", "supply large irrigation schemes.", "supply charges irrigation schemes.", "supply chain irrigation schemes.", "supply chains irrigation schemes."
"supply basin irrigation systems." » "supply drip irrigation systems.", "supply canal irrigation systems.", "supply farm irrigation systems.", "supply chain irrigation systems.", "supply case irrigation systems.", "supply basin irrigation system."

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