Perhaps you should try some spelling variations:
integration theories » integration theorems, integrationstheorie 2, integration theory
irrigation system » irrigation systems, irrigation water, irrigation scheme
trip irrigation » drip irrigation, crop irrigation, grain irrigation
supply crowd » supply growth, supply cost
supply trip » supply tariff, supply trade

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((supply crowd) OR (supply from)) integration theories. ) or ( supply trip irrigation system. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((supply crowd) OR (supply from)) integration theories. ) OR ( supply trip irrigation system. )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((supply crowd) OR (supply from)) integration theories. ) or ( supply trip irrigation system. ))".
• Adding a wildcard symbol may retrieve word variants: (( ((supply crowd) OR (supply from)) integration theories. ) or ( supply trip irrigation system. ))*.