鸡蛋里d肉骨头蛋壳里d小宇宙
[jī dàn lĭ d ròu gú tóu dàn qiào lĭ d xiăo yŭ zhòu]
'Universe hidden within an egg, along with meat bones'. It's metaphorical, expressing an immense, possibly unique, power or characteristic residing inside the person despite a seemingly simple or fragile exterior, just like an eggshell enclosing potentiality.