Perhaps you should try some spelling variations:
irrigation schemes » irrigation scheme, irrigation systems
group integration » grid integration, run integration, through integration
case irrigation » scale irrigation, change irrigation, canal irrigation
support group » support from, support grant
supply case » supply cost, supply chain, supply curve

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( support group integration study. ) or ( supply case irrigation schemes. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( support group integration study. ) OR ( supply case irrigation schemes. )).
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