Perhaps you should try some spelling variations:
"supply cost integration theories." » "supply cost integration theory.", "supply cost integration through.", "supply cost integration efforts.", "supply south integration theories.", "supply tool integration theories.", "supply can integration theories.", "supply costs integration theories."
"supply furrow irrigation system." » "supply farm irrigation system.", "supply crop irrigation system.", "supply flood irrigation system.", "supply furrow irrigation systems.", "supply furrow irrigation water.", "supply furrow irrigation scheme."

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 cost integration theories.") OR ("supply furrow irrigation system."))~.
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