Perhaps you should try some spelling variations:
"support crop irrigation schemes." » "support crop irrigation scheme.", "support crop irrigation systems.", "support drip irrigation schemes.", "support scale irrigation schemes.", "support canal irrigation schemes.", "support crops irrigation schemes.", "support cross irrigation schemes.", "support across irrigation schemes."
"support grid information theory." » "support good information theory.", "support guided information theory.", "support rapid information theory.", "support agri information theory.", "support grant information theory.", "support group information theory."

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