Perhaps you should try some spelling variations:
integration theories » integration theorems, integrationstheorie 2, integration theory
furrow irrigation » farm irrigation, crop irrigation, flood irrigation
irrigation system » irrigation systems, irrigation water, irrigation scheme
deep integration » data integration
support furrow » support from, support follow
supply deep » support deep

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 deep integration theories. ) OR ( support furrow irrigation system. ))~.
• Adding a wildcard symbol may retrieve word variants: (( supply deep integration theories. ) or ( support furrow irrigation system. ))*.