Perhaps you should try some spelling variations:
integration theories » integration theorems, integrationstheorie 2, integration theory
factor integration » facto integration, sector integration, actor interaction
irrigation system » irrigation systems, irrigation water, irrigation scheme
group irrigation » crop irrigation, drip irrigation, from irrigation
support group » support grant
supply factor » supply factors, supply sector

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• Performing a fuzzy search may retrieve terms with similar spellings: (( support group irrigation system. ) or ( supply factor integration theories. ))~.
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