Perhaps you should try some spelling variations:
"international trends economic surveys" » "international trade economic surveys", "international bonds economic surveys", "international treaties economic surveys", "international trends economic studies", "international trends economic systems", "international rents economic surveys", "international roads economic surveys", "international areas economic surveys"
"national poppy economy series" » "national policy economy series", "national power economy series", "national port economy series", "national poppy economics series"

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: (("national poppy economy series") OR ("international trends economic surveys"))~.
• Removing quotes may allow a broader search: (( national poppy economy series ) or ( international trends economic surveys ))~.
• Adding a wildcard symbol may retrieve word variants: (("national poppy economy series") or ("international trends economic surveys"))*.