CJK Tokenization is hard or impossible to do perfectly, especially if you don't know the language or don't want to load megabytes of dictionaries. Here's a simple solution that gets you most of the way.

cjk-tokenization.js

// cjk tokenization snippet:

"hello test 德国 をクリックしてください 안녕하세요 세계"
    .replace(/(\p{Script=Han}|\p{Script=Hiragana}|\p{Script=Katakana}|\p{Script=Hang})/ug, "$1 ")

// inserts spaces after every CJK character, so a normal tokenizer will pick up each character as
// a separate "word". there doesn't seem to be a smarter alternative to this.