Chinese idiom: jiu-niú yī-máo 九牛一毛 

Literal translation: Nine cows, one strand of cow hair. 

This idiom is used to refer to something very small that you wouldn’t notice. It’s very visual: The idea is that you would hardly notice a single strand of cow hair among nine cows. 

Example: Knowledge is endless and unlimited. What I have learnt is just Jiu-niu yi-mao.