Perhaps you should try some spelling variations:
"serie lecturas de clases." » "serie letras de clases.", "serie lectura de clases.", "serie lecturas de clase.", "serie lecturas de bases."
"serie actas la clase." » "serie letras la clase.", "serie fichas la clase.", "serie actis la clase.", "serie actos la clase.", "serie lacteas la clase."
"serie notas mas clase." » "serie nota mas clase.", "serie notas tras clase.", "serie notas a clase.", "serie notas las clases.", "serie notas mis clases.", "serie notas las class."

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 mas clase.") or ("serie actas la clase."))) or ("serie lecturas de clases."))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (((("serie notas mas clase.") OR ("serie actas la clase."))) OR ("serie lecturas de clases."))*.
• Removing quotes may allow a broader search: (((( serie notas mas clase. ) or ( serie actas la clase. ))) or ( serie lecturas de clases. ))*.