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