Perhaps you should try some spelling variations:
"seis estudios hispana." » "seis estudios hispano.", "seis estudios hispanicos.", "seis estudios historia.", "los estudios hispana.", "dos estudios hispana.", "dios estudios hispana."
"series estudios urbanos." » "tres estudios urbanos.", "leyes estudios urbanos.", "sociales estudios urbanos.", "series estudio urbanos.", "series estudios peruanoss.", "series estudios hispanos."
"serie estudios urbano." » "serie estudio urbano.", "serie estudios peruanos.", "serie 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 ("serie estudios urbano."))) or ("seis estudios hispana."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("series estudios urbanos.") OR ("serie estudios urbano."))) OR ("seis estudios hispana."))*.
• Removing quotes may allow a broader search: (((( series estudios urbanos. ) or ( serie estudios urbano. ))) or ( seis estudios hispana. ))*.