Perhaps you should try some spelling variations:
international policies » international politics, international prices, international policy
irrigation scheme » irrigation systems
grid irrigation » drip irrigation, syria irrigation, crop irrigation
supply china » supply chains, supply chain
support grid » support agri, support grant, support group

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( supply china international policies. ) or ( support grid irrigation scheme. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( supply china international policies. ) OR ( support grid irrigation scheme. )).
• Adding a wildcard symbol may retrieve word variants: (( supply china international policies. ) or ( support grid irrigation scheme. ))*.