Perhaps you should try some spelling variations:
"supply chain integration theories." » "supply chain integration theory.", "supply chain integration through.", "supply chain integration efforts.", "supply trade integration theories.", "supply data integration theories.", "supply grid integration theories."
"support migrant integrating services." » "support migrant integrated services.", "support migrant testing services.", "support migrant integrating policies.", "support migrant integration services.", "support market integrating services.", "support grant integrating services."

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"supply chain integration theories.\") OR (\"support migrant integrating services.\"))~".
• Removing quotes may allow a broader search: (( supply chain integration theories. ) OR ( support migrant integrating services. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply chain integration theories.") OR ("support migrant integrating services."))*.