Perhaps you should try some spelling variations:
"dios estudios americanos." » "dios estudios latinoamericanos.", "dos estudios americanos.", "los estudios americanos.", "otros estudios americanos."
"series estudio urbano." » "series estudios urbano.", "serie estudio urbano.", "serie estudios urbano.", "series estudios urbanos."
"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 estudio urbano.") OR ("series espacio urbano."))) or ("dios estudios americanos."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("series estudio urbano.") OR ("series espacio urbano."))) OR ("dios estudios americanos."))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"series estudio urbano.\") OR (\"series espacio urbano.\"))) or (\"dios estudios americanos.\"))*".
• Removing quotes may allow a broader search: (((( series estudio urbano. ) OR ( series espacio urbano. ))) or ( dios estudios americanos. ))*.