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."
"versus espacio urbano." » "versus estado urbano.", "versus ignacio urbano.", "versus espacio urbanismo."

Try widening your search to All Fields.

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

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