Perhaps you should try some spelling variations:
irrigation scheme » irrigation systems
export water » export matter, export after, export pattern
export rates » export ratios, export ratio, export bases
import state » import share, port state, import shares
banks series » bank series, banks serve, banking series

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( ((export water) OR (export rates)) irrigation scheme. ) or ( import state banks series. ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( ((export water) OR (export rates)) irrigation scheme. ) OR ( import state banks series. )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( ((export water) OR (export rates)) irrigation scheme. ) or ( import state banks series. ))".
• Adding a wildcard symbol may retrieve word variants: (( ((export water) OR (export rates)) irrigation scheme. ) or ( import state banks series. ))*.