Perhaps you should try some spelling variations:
"international ports economy series" » "international airports economy series", "international poverty economy series", "international efforts economy series", "international ports economics series", "international porn economy series", "international sports economic series", "international export economy series"
"regional political autonomy series" » "regional politics autonomy series", "national political autonomy series", "regional policy autonomy series", "regional political economy series", "regional political authority series", "regional political astronomy series", "regional political autonomy states", "regional political autonomy survey"

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: (("regional political autonomy series") or ("international ports economy series"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("regional political autonomy series") OR ("international ports economy series")).
• Removing quotes may allow a broader search: (( regional political autonomy series ) or ( international ports economy series )).
• Adding a wildcard symbol may retrieve word variants: (("regional political autonomy series") or ("international ports economy series"))*.