Perhaps you should try some spelling variations:
"tres estudios criticos." » "tres estudios juridicos.", "otros estudios criticos.", "los estudios criticos.", "dios estudios criticos."
"dos estudios criticos." » "dos estudios juridicos.", "los estudios criticos."
"serie estudos hispanos." » "serie estudios hispano.", "serie estudios hispanicos.", "serie estilo hispano.", "serie estudios hispanos.", "series estudios hispanos.", "serie estado hispanos."

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