Perhaps you should try some spelling variations:
"serie lecturas de clacsos." » "serie letras de clacsos.", "serie lectura de clacsos.", "serie lecturas de clacso.", "serie lecturas de casos.", "serie lecturas de clases."
"serie notas la clase." » "serie actas la clase.", "serie poetas la clase.", "serie notas mas clase.", "serie notas de clase.", "serie notas la case.", "serie notas ly clase.", "serie notas la clas."
"serie notas a clase." » "serie actas a clase.", "serie notas de clase.", "serie notas en clase.", "serie notas a case.", "serie notas y clase.", "serie notas a clas."

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

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