Perhaps you should try some spelling variations:
"serie estudios peruanos." » "serie estudios americanos.", "serie estudios ensayos.", "serie estudios cervantinos."
"leyes estudioss urbano." » "leyes estudios urbano.", "leyes estudio urbano.", "ley estudios urbano."
"series estudios urbanos." » "seis estudios urbanos.", "tres estudios urbanos.", "leyes estudios urbanos."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("leyes estudioss urbano.") or ((("series estudios urbanos.") or ("serie estudios peruanos."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("leyes estudioss urbano.") OR ((("series estudios urbanos.") OR ("serie estudios peruanos."))))*.
• Removing quotes may allow a broader search: (( leyes estudioss urbano. ) or ((( series estudios urbanos. ) or ( serie estudios peruanos. ))))*.