Perhaps you should try some spelling variations:
"supply cost integration theory." » "supply cost integration through.", "supply cost information theory.", "supply cost innovation theory.", "supply post integration theory.", "supply test integration theory.", "supply about integration theory.", "supply costs integration theory."
"supply firms irrigation schemes." » "supply firms irrigation scheme.", "supply firms irrigation systems.", "supply farm irrigation schemes.", "supply field irrigation schemes.", "supply from irrigation schemes.", "supply reforms irrigation schemes.", "support firms irrigation 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 cost integration theory.") or ("supply firms irrigation schemes."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply cost integration theory.") OR ("supply firms irrigation schemes.")).
• Removing quotes may allow a broader search: (( supply cost integration theory. ) or ( supply firms irrigation schemes. )).
• Adding a wildcard symbol may retrieve word variants: (("supply cost integration theory.") or ("supply firms irrigation schemes."))*.