Perhaps you should try some spelling variations:
"international africa's economy series" » "international african economy series", "international prices economy series", "international airways economy series", "international africa's economic series", "international america's economic series", "international africa's economics series"
"international self autonomy survey" » "international sale autonomy survey", "international silk autonomy survey", "international sales autonomy survey", "international user autonomy survey"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("international self autonomy survey") or ("international africa's economy series"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("international self autonomy survey") OR ("international africa's economy series")).
• Removing quotes may allow a broader search: (( international self autonomy survey ) or ( international africa's economy series )).
• Adding a wildcard symbol may retrieve word variants: (("international self autonomy survey") or ("international africa's economy series"))*.