Perhaps you should try some spelling variations:
"dios estudios americanos." » "dios estudios latinoamericanos.", "dos estudios americanos.", "los estudios americanos.", "otros estudios americanos."
"dios estudios peruanos." » "dios estudios urbanos.", "dios estudios ensayos.", "dios estudios cervantinos.", "dos estudios peruanos.", "los estudios peruanos.", "otros 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 ((("dios estudios peruanos.") OR ("dios estudios americanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("series estudios hispano.") OR ((("dios estudios peruanos.") OR ("dios estudios americanos."))))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"series estudios hispano.\") or (((\"dios estudios peruanos.\") OR (\"dios estudios americanos.\"))))*".
• Removing quotes may allow a broader search: (( series estudios hispano. ) or ((( dios estudios peruanos. ) OR ( dios estudios americanos. ))))*.