Perhaps you should try some spelling variations:
"supply channels irrigation scheme." » "supply change irrigation scheme.", "supply canal irrigation scheme.", "supply channels information scheme.", "supply channels irrigation systems."
"supply chains insulation schemes." » "supply chains regulation schemes.", "supply chains integration schemes.", "supply chains irrigation schemes.", "supply chains innovation schemes.", "supply chains innovations schemes.", "supply cable insulation schemes.", "supply chain insulation schemes."

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

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