Perhaps you should try some spelling variations:
"supply chains immigration policies." » "supply chains immigration policy.", "supply chains migration policy.", "supply chinese immigration policies.", "supply chain migration policies.", "supply chain integration policies.", "supply chain immigration policies."
"supply content integration theories." » "supply content integration theorems.", "supply content integrationstheorie 2.", "supply content integration theory.", "supply continental integration theories.", "supply connectes integration theories.", "supply content moderation theories.", "supply contract integration theories.", "supply cote integration theories.", "supply current integration theories."

Try widening your search to All Fields.

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

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