Perhaps you should try some spelling variations:
"support trade integration theories." » "support trade integration theorems.", "support trade integrationstheorie 2.", "support trade integration theory.", "support trainer integration theories.", "export trade integration theories.", "import trade integration theories."
"support grid integration schemes." » "support grid integration schengen.", "support grid irrigation schemes.", "support grid integration regimes.", "support agri integration schemes.", "support grant integration schemes.", "support group integration schemes."

Try widening your search to All Fields.

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