take sb . by surprise
It's a Chinese idiom. Pinyin is y ǎ NQ í w ú B è I, which means to take advantage of the enemy's unprepared attack. It's from Sun Tzu Ji pian.
Idiom explanation
Said to take advantage of the enemy's defenseless when the raid.
The origin of Idioms
"Sun Tzu Ji Pian": "attack it unprepared, surprise."
take sb . by surprise
Without skin, how can hair be attached - pí zhī bù cún,máo jiāng yān fù
feel as if a knife were piercing one 's heart - xīn rú dāo jù