Perhaps you should try some spelling variations:
"international references economic surveys" » "international reference economic surveys", "internationally references economic surveys", "international conferences economic surveys", "international references economic studies", "international references economic systems"
"international treaty economics series" » "international treaties economics series", "international trade economics series", "international trends economics series", "international real economics series", "international theory economics series", "international trek economics series"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("international references economic surveys") or ("international treaty economics series"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international references economic surveys") OR ("international treaty economics series"))*.
• Removing quotes may allow a broader search: (( international references economic surveys ) or ( international treaty economics series ))*.