Perhaps you should try some spelling variations:
"supply race immigration policies." » "supply race immigration policy.", "supply race migration policy.", "supply scale immigration policies.", "supply mass immigration policies.", "supply more immigration policies.", "supply rates immigration policies.", "supply reach immigration policies.", "supply case immigration policies."
"supply cost sanitation services." » "supply good sanitation services.", "supply poor sanitation services.", "supply food sanitation services.", "supply costs sanitation services."

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (("supply race immigration policies.") OR ("supply cost sanitation services."))~.
• Removing quotes may allow a broader search: (( supply race immigration policies. ) or ( supply cost sanitation services. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply race immigration policies.") or ("supply cost sanitation services."))*.