Perhaps you should try some spelling variations:
"psychology case studies." » "psychology latin studies.", "psychology spain studies."
"sociology spain studies." » "sociology latin studies.", "sociology spain asturias.", "sociology spain sources.", "sociology pace studies."
"psychology car estudios." » "psychology early estudios.", "psychology peru estudios.", "psychology _ estudios.", "psychology c estudios.", "psychology a estudios.", "psychology sur estudios."

Try widening your search to All Fields.

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• Performing a fuzzy search may retrieve terms with similar spellings: (("psychology car estudios.") or ((("psychology case studies.") or ("sociology spain studies."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("psychology car estudios.") OR ((("psychology case studies.") OR ("sociology spain studies.")))).
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• Adding a wildcard symbol may retrieve word variants: (("psychology car estudios.") or ((("psychology case studies.") or ("sociology spain studies."))))*.