Perhaps you should try some spelling variations:
"aei studies on series round negotiations." » "aei studies on series loan negotiations.", "aei studies on series loan negotiation.", "aei studies on series four negotiations.", "aei studies on series land negotiations."
"aei studies on service trade negotiations." » "aei studies on services trade negotiations."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("aei studies on service trade negotiations.") or ("aei studies on series round negotiations."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("aei studies on service trade negotiations.") OR ("aei studies on series round negotiations."))*.
• Removing quotes may allow a broader search: (( aei studies on service trade negotiations. ) or ( aei studies on series round negotiations. ))*.