Perhaps you should try some spelling variations:
"political economic" » "political economy", "ecological economics"
"political ecology" » "political economy", "political sociology"
"policy economic" » "policy macroeconomic"
"policy economics" » "policy macroeconomics"

Try widening your search to All Fields.

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

• If you are trying to use Boolean operators, they must be ALL CAPS: (((("political economic") OR ("political ecology"))) OR ((("policy economic") OR ("policy economics")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"political economic\") or (\"political ecology\"))) or (((\"policy economic\") OR (\"policy economics\"))))".
• Removing quotes may allow a broader search: (((( political economic ) or ( political ecology ))) or ((( policy economic ) OR ( policy economics )))).
• Adding a wildcard symbol may retrieve word variants: (((("political economic") or ("political ecology"))) or ((("policy economic") OR ("policy economics"))))*.