Perhaps you should try some spelling variations:
immigration policies » immigration policy, migration policy
integration theories » integration theorems, integrationstheorie 2, integration theory
now immigration » new immigration, net immigration, anti immigration
how integration » new integration, how interaction, die integration
supply now » supply crowd, supply donor

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 now immigration policies. ) OR ( supply how integration theories. ))~.
• Adding a wildcard symbol may retrieve word variants: (( supply now immigration policies. ) or ( supply how integration theories. ))*.