zhuīgēnjiūdǐr
ㄓㄨㄟ ㄍㄣ ㄐㄧㄡ ㄉㄧˇ ˙ㄦ
Simplified 追根究底儿
Taivo → Settings → Partner inbox → Make the link. It stays in this browser.
Keep 追根究底兒 and it comes back until you know it.