Perhaps you should try some spelling variations:
irrigation schemes » irrigation scheme, irrigation systems
planning services » banking services
ratio irrigation » water irrigation, basin irrigation, grain irrigation
das planning » dam planning, gas planning, deals planning
import das » import data, import bans, import tax

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( export ratio irrigation schemes. ) or ( import das planning services. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( export ratio irrigation schemes. ) OR ( import das planning services. )).
• Adding a wildcard symbol may retrieve word variants: (( export ratio irrigation schemes. ) or ( import das planning services. ))*.