Perhaps you should try some spelling variations:
"serie maestros peruanos." » "serie maestro peruano.", "serie maestros alumnos.", "serie maestria peruanos.", "ser maestros peruanos.", "serie maestraia peruanos."
"serie studias urbanos." » "serie estudios urbano.", "serie studia urbanos.", "serie estudios urbanos.", "series estudios urbanos."
"tres estudios urbanos." » "otros estudios urbanos.", "los estudios urbanos.", "dos estudios urbanos."

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