Perhaps you should try some spelling variations:
"serie cartas de bases." » "serie actas de bases.", "serie arte de bases.", "serie notas de bases.", "serie artes de bases.", "serie arts de bases."
"serie cartas de clase." » "serie actas de clase.", "serie arte de clase.", "serie notas de clase.", "serie artes de clase.", "serie arts de clase.", "serie cartas de clacso.", "serie cartas la clase."
"serie carta de clase." » "serie arte de clase.", "serie art de clase.", "serie carta de clacso.", "serie carta la clase."

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("serie cartas de bases.") or ((("serie cartas de clase.") or ("serie carta de clase."))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("serie cartas de bases.") OR ((("serie cartas de clase.") OR ("serie carta de clase.")))).
• Removing quotes may allow a broader search: (( serie cartas de bases. ) or ((( serie cartas de clase. ) or ( serie carta de clase. )))).
• Adding a wildcard symbol may retrieve word variants: (("serie cartas de bases.") or ((("serie cartas de clase.") or ("serie carta de clase."))))*.