尋根究柢 [寻－－－]

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Pinyin xún gēn jiū dǐ

Definitions (粵典–words.hk)
  1. 語句
    追求​根底​。​一般​指追問​一件​事​嘅​原由​。
    to inquire deeply into
  2. 參看
    尋根究底