Perhaps you should try some spelling variations:
irrigation schemes » irrigation scheme, irrigation systems
irrigation system » irrigation systems, irrigation water, irrigation scheme
surge irrigation » large irrigation, surface irrigation, scale irrigation
de irrigation » de l'irrigation, led irrigation, fed irrigation
supply surge » supply curve, supply sources, supply curves
supply de » supply _, supply a, supply 3

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 de irrigation schemes. ) OR ( supply surge irrigation system. ))~.
• Adding a wildcard symbol may retrieve word variants: (( supply de irrigation schemes. ) or ( supply surge irrigation system. ))*.