Hi Christian,
I made up some data
SeedRandom[1];
words = RandomWord["CommonWords", 20, Language -> "German"] //
Join[#, {"树", "指", "都", "鱼", "刻", "朵", "今天"}] &
includeChars = {CharacterRange["A", "Z"], CharacterRange["a", "z"],
CharacterRange["0", "9"], "!"} // Flatten;
words // Select[! StringContainsQ[#, Except[includeChars]] &]
(*
{"Verhandlungsgeschick", "baggern", "Separation", "jure",
"Rechenschritt", "Kriegsbereit", "Riesenteleskop", "Statusbit",
"Dreieck", "cineastisch", "demselben", "Andalusier"}
*)