Perhaps you should try some spelling variations:
"Policy research workshop paper" » "Policy research workshop papers", "Policy research workshop panel", "Policy research workshop papm"
"policy research working papers" » "policy research working paper"

Try widening your search to All Fields.

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("Policy research workshop paper") OR ("policy research working papers")).
• Removing quotes may allow a broader search: (( Policy research workshop paper ) or ( policy research working papers )).
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