Perhaps you should try some spelling variations:
"dos estudios hispanic." » "dos estudios hispanicos.", "dos estudios hispano.", "dos studies hispanic.", "los estudios hispanic."
"series d'estudis urbans." » "series estudios urbans.", "serie estudios urbans.", "serie estudos urbans.", "series estudios urbanos.", "series estudios urbano."
"serie estudio urbano." » "serie estudios urbano.", "serie estudios urbanos.", "serie espacio urbano.", "series estudios urbano.", "serie studia urbano."

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

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