Perhaps you should try some spelling variations:
tsarist irrigation » saline irrigation, saving irrigation, soviet irrigation
chains irrigation » change irrigation, grain irrigation, canal irrigation
irrigation scheme » irrigation systems
supply tsarist » supply tariff, supply tourism
supply chains » supply chain

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

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