Perhaps you should try some spelling variations:
"supply school integrating theories." » "supply school integration theories.", "supply school integrating theory.", "supply school interpolating theories.", "supply school reintegration theories.", "supply school interactions theories.", "supplies school integrating theories.", "support school integrating theories.", "supply shock integrating theories."
"supply curve irrigation scheme." » "supply curve irrigation systems.", "supply surge irrigation scheme.", "supply large irrigation scheme.", "supply crop irrigation scheme."

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