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

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