Perhaps you should try some spelling variations:
"supply factor integration theories." » "supply factor integration theory.", "supply factor integration through.", "supply factor integration efforts.", "supply facto integration theories.", "supply sector integration theories.", "supply faculty integration theories.", "supply factors integration theories.", "supply water integration theories."
"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 group irrigation schemes.", "support cross irrigation schemes."

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