Perhaps you should try some spelling variations:
integration theories » integration theorems, integrationstheorie 2, integration theory
irrigation scheme » irrigation systems
cost integration » post integration, test integration, about integration
crop irrigation » drip irrigation, scale irrigation, canal irrigation
supply crop » supply crowd, supply from, supply europe
supply cost » supply costs

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (( supply crop irrigation scheme. ) OR ( supply cost integration theories. ))~.
• Adding a wildcard symbol may retrieve word variants: (( supply crop irrigation scheme. ) or ( supply cost integration theories. ))*.