Perhaps you should try some spelling variations:
"leyes estudios hispana." » "leyes estudios hispano.", "leyes estudios hispanicos.", "leyes estudios historia.", "los estudios hispana.", "seis estudios hispana.", "tres estudios hispana."
"serie estudios urbano." » "serie estudios urbanos.", "serie estudio urbano.", "serie estudios peruanos."
"series estudios urbano." » "series estudios urbanos.", "series estudio urbano.", "series estudios peruanos.", "seis estudios urbano.", "tres estudios urbano.", "sociales estudios urbano."

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