Perhaps you should try some spelling variations:
"dos estudios americanos." » "dos estudios latinoamericanos.", "los estudios americanos."
"dos estudios peruanos." » "dos estudios urbanos.", "dos estudios ensayos.", "dos estudios cervantinos.", "los estudios peruanos."
"series estudios hispano." » "serie estudios hispano.", "seis estudios hispano.", "tres estudios hispano."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("series estudios hispano.") or ((("dos estudios peruanos.") OR ("dos estudios americanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("series estudios hispano.") OR ((("dos estudios peruanos.") OR ("dos estudios americanos."))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"series estudios hispano.\") or (((\"dos estudios peruanos.\") OR (\"dos estudios americanos.\"))))*".
• Removing quotes may allow a broader search: (( series estudios hispano. ) or ((( dos estudios peruanos. ) OR ( dos estudios americanos. ))))*.