水仙不开花/ 水仙不開花 shuǐxiānbùkāihuā to play dumb
a 歇后语 xiēhòuyǔ (two-part allegorical saying) meaning to pretend not to know; specifically meaning 装蒜 zhuāngsuàn. Derived from the fact that a narcissus that has not bloomed looks almost identical to a head of garlic.