Perhaps you should try some spelling variations:
"sociales estudio urbano." » "sociales estudios urbano.", "sociales espacio urbano."
"series estudios urbanos." » "serie estudios urbanos.", "seis estudios urbanos.", "tres estudios urbanos.", "series estudios peruanoss.", "series estudios hispanos.", "series d'estudis urbanss."
"series estudios urbano." » "serie estudios urbano.", "seis estudios urbano.", "tres estudios urbano.", "series estudios peruanos.", "series estudios hispano.", "series d'estudis urbans."

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: (((("series estudios urbanos.") or ("series estudios urbano."))) or ("sociales estudio urbano."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("series estudios urbanos.") OR ("series estudios urbano."))) OR ("sociales estudio urbano.")).
• Removing quotes may allow a broader search: (((( series estudios urbanos. ) or ( series estudios urbano. ))) or ( sociales estudio urbano. )).
• Adding a wildcard symbol may retrieve word variants: (((("series estudios urbanos.") or ("series estudios urbano."))) or ("sociales estudio urbano."))*.