Perhaps you should try some spelling variations:
"supply trade integrationstheorie 2." » "supply der integrationstheorie 2.", "supply eine integrationstheorie 2.", "supply traditionelle integrationstheorie 2.", "supply trade integrationstheorie fur.", "supply trade integration theories.", "supply trade interpretationstheorie 2.", "supply case integrationstheorie 2."
"policy international migration soziale." » "policy international cooperation soziale.", "policy interventions migration soziale.", "policy intervention migration soziale.", "policy international migration social.", "policy international migration sowie.", "policy international integration soziale."

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 trade integrationstheorie 2.") OR ("policy international migration soziale."))~.
• Removing quotes may allow a broader search: (( supply trade integrationstheorie 2. ) or ( policy international migration soziale. ))~.
• Adding a wildcard symbol may retrieve word variants: (("supply trade integrationstheorie 2.") or ("policy international migration soziale."))*.