Perhaps you should try some spelling variations:
integration efforts » international efforts, conservation efforts
rural irrigation » murray irrigation, canal irrigation, gray irrigation
supply rural » supply curve
export bans » export base, export bias, import bans
export can » exports can, export ban, export day
systems. » system.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( supply rural irrigation systems. ) or ( ((export can) OR (export bans)) integration efforts. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( supply rural irrigation systems. ) OR ( ((export can) OR (export bans)) integration efforts. )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( supply rural irrigation systems. ) or ( ((export can) OR (export bans)) integration efforts. ))".
• Adding a wildcard symbol may retrieve word variants: (( supply rural irrigation systems. ) or ( ((export can) OR (export bans)) integration efforts. ))*.