Perhaps you should try some spelling variations:
"tres estudios peruanoss." » "tres estudios peruanos.", "tres estudios urbanos.", "otros estudios peruanoss.", "los estudios peruanoss.", "dos estudios peruanoss."
"series estudio urbanos." » "series estudios urbanos.", "series estudio urbano.", "series estudios peruanos.", "serie estudio urbanos.", "serie estudios urbanos.", "senales estudio urbanos."
"series estudios urbano." » "serie estudios urbano.", "seis estudios urbano.", "leyes estudios urbano.", "series estudios urbanos.", "series estudio urbano.", "series estudios peruanos.", "serie estudioss urbano.", "senales 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: (((("tres estudios peruanoss.") or ("series estudio urbanos."))) or ("series estudios urbano."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("tres estudios peruanoss.") OR ("series estudio urbanos."))) OR ("series estudios urbano."))*.
• Removing quotes may allow a broader search: (((( tres estudios peruanoss. ) or ( series estudio urbanos. ))) or ( series estudios urbano. ))*.