Perhaps you should try some spelling variations:
irrigation schemes » irrigation scheme, irrigation systems
sector integration » social integration
integration power » integration some, integration process, international power
supply crowd » supply growth, supply cost
supply how » supply shock

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 crowd) OR (supply how)) irrigation schemes. ) OR ( supply sector integration power. ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((supply crowd) OR (supply how)) irrigation schemes. ) or ( supply sector integration power. ))~".
• Adding a wildcard symbol may retrieve word variants: (( ((supply crowd) OR (supply how)) irrigation schemes. ) or ( supply sector integration power. ))*.