Perhaps you should try some spelling variations:
"supply grid integration theories." » "supply grid integration theory.", "supply grid integration through.", "supply grid integration efforts.", "supply trade integration theories.", "supply _ integration theories.", "supply data integration theories.", "supply crowd integration theories.", "support grid integration theories."
"supply grid immigration policies." » "supply grid immigration policy.", "supply grid migration policy.", "supply gross immigration policies.", "supply from immigration policies.", "supply _ immigration policies.", "supply crowd immigration policies.", "support grid immigration policies."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("supply grid integration theories.") OR ("supply grid immigration policies."))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"supply grid integration theories.\") OR (\"supply grid immigration policies.\"))*".
• Removing quotes may allow a broader search: (( supply grid integration theories. ) OR ( supply grid immigration policies. ))*.