Perhaps you should try some spelling variations:
"supply gross immigration policy." » "supply gross migration policy.", "supply gross emigration policy.", "supply mass immigration policy.", "supply from immigration policy.", "supply growth immigration policy.", "supply costs immigration policy.", "supply cost immigration policy."
"support aid conservation efforts." » "support land conservation efforts.", "support bird conservation efforts.", "support wild conservation efforts.", "support add conservation efforts.", "support david conservation efforts.", "support a conservation efforts."

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

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