Perhaps you should try some spelling variations:
"leyes estudios peruanoss." » "leyes estudios peruanos.", "series estudios peruanoss.", "los estudios peruanoss.", "seis estudios peruanoss."
"dos estudios urbanos." » "dos estudio urbanos.", "dos estudios peruanoss.", "dos estudios hispanos.", "los estudios urbanos."
"dios estudios urbano." » "dios estudio urbano.", "dios estudios peruanos.", "dios estudios hispano.", "los estudios urbano.", "otros estudios urbano.", "altos estudios urbano."

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

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