Perhaps you should try some spelling variations:
"series estudios cervantinos." » "series estudios mercantiles.", "series estudios criticos.", "series estudios andinos.", "serie estudios cervantinos.", "tres estudios cervantinos.", "leyes estudios cervantinos."
"seis estudios urbano." » "seis estudio urbano.", "seis estudios peruanos.", "seis estudios hispano.", "los estudios urbano.", "dos estudios urbano.", "dios estudios urbano."
"seis estudios urbanos." » "seis estudio urbanos.", "seis estudios peruanoss.", "seis estudios hispanos.", "los estudios urbanos.", "dos estudios urbanos.", "dios estudios urbanos."

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 cervantinos.") or ((("seis estudios urbano.") or ("seis estudios urbanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("series estudios cervantinos.") OR ((("seis estudios urbano.") OR ("seis estudios urbanos."))))*.
• Removing quotes may allow a broader search: (( series estudios cervantinos. ) or ((( seis estudios urbano. ) or ( seis estudios urbanos. ))))*.