Perhaps you should try some spelling variations:
irrigation system » irrigation systems, irrigation water, irrigation scheme
planning series » planning services, planning service, learning series
state planning » strategic planning
improve state » improving state, improve water, improve care
export scale » export share, export sales, export shares

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

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