Perhaps you should try some spelling variations:
"supply chain integration theory." » "supply chain integration through.", "supply chain information theory.", "supply chain integration report.", "supply trade integration theory.", "supply data integration theory.", "supply grid integration theory."
"supply crowd irrigation systems." » "supply crop irrigation systems.", "supply flood irrigation systems.", "supply from irrigation systems.", "supply growth irrigation systems.", "supply cost irrigation systems.", "supply how irrigation systems.", "supply crowd irrigation system."

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply chain integration theory.") OR ("supply crowd irrigation systems."))~.
• Removing quotes may allow a broader search: (( supply chain integration theory. ) or ( supply crowd irrigation systems. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply chain integration theory.") or ("supply crowd irrigation systems."))*.