Perhaps you should try some spelling variations:
"series estudios urbano." » "serie estudios urbano.", "seis estudios urbano.", "tres estudios urbano.", "series estudios urbanos.", "series estudio urbano.", "series estudios peruanos."
"reales estudios urbano." » "reales estudios urbanos.", "reales estudio urbano.", "reales estudios peruanos.", "rurales estudios urbano.", "locales estudios urbano."
"series espacio urbano." » "series spain urbano.", "versus espacio urbano.", "sociales espacio urbano.", "series espacio urbanismo."

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (((("series espacio urbano.") or ("series estudios urbano."))) or ("reales estudios urbano."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("series espacio urbano.") OR ("series estudios urbano."))) OR ("reales estudios urbano."))*.
• Removing quotes may allow a broader search: (((( series espacio urbano. ) or ( series estudios urbano. ))) or ( reales estudios urbano. ))*.