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

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