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