Perhaps you should try some spelling variations:
"serie estudios peruanoss." » "serie estudios peruanos.", "serie estudios urbanos."
"series estudio urbano." » "series estudios urbano.", "serie estudio urbano.", "senales estudio urbano.", "series estudios urbanos.", "series espacio urbano."
"serret estado cubano." » "serie estado cubano.", "herrera estado cubano.", "serret estela cubano."

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