Perhaps you should try some spelling variations:
"health sciences, geography, environment, planning" » "health science, geography, environment, planning"
"earth sciences, geography, environment, planning" » "earth science, geography, environment, planning"

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• If you are trying to use Boolean operators, they must be ALL CAPS: (("health sciences, geography, environment, planning") OR ("earth sciences, geography, environment, planning")).
• Removing quotes may allow a broader search: (( health sciences, geography, environment, planning ) or ( earth sciences, geography, environment, planning )).
• Adding a wildcard symbol may retrieve word variants: (("health sciences, geography, environment, planning") or ("earth sciences, geography, environment, planning"))*.