trace back to the sources
The Chinese idiom, Pinyin is Zhu ī B ě nqi ó ngyu á, which means to find out the source of things. From the romance of Hong Xiuquan.
Idiom explanation
Poor: seeking to the end.
The origin of Idioms
In the second chapter of the romance of Hong Xiuquan, "it is true that Chinese merchants have been selling opium in search of its source."
trace back to the sources
a pasture on which cattle can graze - cháng lín fēng cǎo
one 's heart ached as if pierced by ten thousand arrows - wàn jiàn cuán xīn