Perhaps you should try some spelling variations:
integration theories » integration theorems, integrationstheorie 2, integration theory
irrigation schemes » irrigation scheme, irrigation systems
canal irrigation » scale irrigation
support canal » support can, support data, support bank
support grid » support agri, support grant, support group

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• Performing a fuzzy search may retrieve terms with similar spellings: (( support grid integration theories. ) or ( support canal irrigation schemes. ))~.
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