Perhaps you should try some spelling variations:
international ecological » international technological, international psychological, international economics
"international political economy series" » "international policy economy series", "international political economics series"
"International ecological economic services" » "International ecological economics services", "International political economic services", "International economics economic services", "International ecological economics series", "International ecological ecological services", "International ecological economic studies"

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