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

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 hispanos.") OR ("series estudios hispano."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("tres estudios criticos.") OR ((("series estudios hispanos.") OR ("series estudios hispano.")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"tres estudios criticos.\") or (((\"series estudios hispanos.\") OR (\"series estudios hispano.\"))))".
• Removing quotes may allow a broader search: (( tres estudios criticos. ) or ((( series estudios hispanos. ) OR ( series estudios hispano. )))).
• Adding a wildcard symbol may retrieve word variants: (("tres estudios criticos.") or ((("series estudios hispanos.") OR ("series estudios hispano."))))*.