Each word in the following list corresponds to one letter:
rôle résumé Jalapeño xoriço ö führer
The combination of letters can be represented as ----uu
Here, the -'s represent the missing letters. The last two letters are u's.
Hint 1 :
The meaning or language of the words has nothing to do with the letters
Hint 2 :
Only some letters in the words are useful. The combination of letters wouldn't change if the other non-important words are replaced/deleted.