Perhaps you should try some spelling variations:
"international political ecological services" » "international policy ecological services", "international political technological services", "international political ecologies services", "international political economic services", "international political hydrological services", "international political clinical services", "international political meteorological services"
"international prices economy series" » "international prices economic series", "international driven economy series", "international rich economy series", "international prices economics series"

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