Perhaps you should try some spelling variations:
"estudios peruanos desde." » "estudios urbanos desde.", "estudios americanos desde.", "estudios ensayos desde.", "estudios peruanos de.", "estudios peruanos del.", "estudios peruanos jose."
"estudios humanos desde." » "estudios urbanos desde.", "estudios humanisticos desde.", "estudios ensayos desde.", "estudios humanos de."
"estudios maior serie." » "estudios marcial serie.", "estudios nativos serie.", "estudios maior series.", "estudios mayo serie.", "estudios minor serie."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (((("estudios humanos desde.") OR ("estudios peruanos desde."))) or ("estudios maior serie."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("estudios humanos desde.") OR ("estudios peruanos desde."))) OR ("estudios maior serie."))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"estudios humanos desde.\") OR (\"estudios peruanos desde.\"))) or (\"estudios maior serie.\"))*".
• Removing quotes may allow a broader search: (((( estudios humanos desde. ) OR ( estudios peruanos desde. ))) or ( estudios maior serie. ))*.