Perhaps you should try some spelling variations:
"estudios humanos serie." » "estudios urbanos serie.", "estudios peruanos serie.", "estudios humanisticos serie.", "estudios humanas serie.", "estudios humanos desde."
"estudios mas series." » "estudios a series.", "estudios maior series.", "estudios de series.", "estudios las series.", "estudios das series.", "estudios mater series."
"estudio las redes." » "estudio la redes.", "estudiar las redes.", "estudio a redes.", "estudio las reyes."

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

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