Perhaps you should try some spelling variations:
"international political economic services" » "international policy economic services", "international political economy services", "international ecological economics services", "international political economics series", "international political economic studies", "international political economic surveys"
"international seminar ecological services" » "international series ecological services", "international standard ecological services", "international mining ecological services", "international seminar hydrological services", "international seminar clinical services", "international seminar meteorological services", "international social ecological services"

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