Perhaps you should try some spelling variations:
"export trade integration theories." » "export trade integration theorems.", "export trade integrationstheorie 2.", "export trade integration theory.", "export taxes integration theories.", "export base integration theories.", "export tax integration theories."
"support funds integration series." » "support funds integration services.", "support funds interaction series.", "support funds integration server.", "support und integration series.", "support eu's integration series.", "support firms integration series.", "support falls integration series.", "support fda integration series."

Try widening your search to All Fields.

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("support funds integration series.") or ("export trade integration theories."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("support funds integration series.") OR ("export trade integration theories.")).
• Removing quotes may allow a broader search: (( support funds integration series. ) or ( export trade integration theories. )).
• Adding a wildcard symbol may retrieve word variants: (("support funds integration series.") or ("export trade integration theories."))*.