Perhaps you should try some spelling variations:
"tres estudios criticos." » "tres estudios juridicos.", "otros estudios criticos.", "los estudios criticos.", "dos estudios criticos."
"serie estudios hispanos." » "serie estudios hispanicos.", "serie estudios espanoles.", "serie estudios lesbianos."
"series estudios hispano." » "seis estudios hispano.", "leyes estudios hispano.", "sociales estudios hispano."

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: (("tres estudios criticos.") or ((("series estudios hispano.") or ("serie estudios hispanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("tres estudios criticos.") OR ((("series estudios hispano.") OR ("serie estudios hispanos.")))).
• Removing quotes may allow a broader search: (( tres estudios criticos. ) or ((( series estudios hispano. ) or ( serie estudios hispanos. )))).
• Adding a wildcard symbol may retrieve word variants: (("tres estudios criticos.") or ((("series estudios hispano.") or ("serie estudios hispanos."))))*.