A hair from nine cattles.
Meaning: Something that is unimportant.
My informant told me that this saying he learned from his older brothers or mother when he was in elementary school. This saying was used to describe the unimportance of an object.
He remembers that his brother used to say this to make him feel bad about accomplishing something or by taking something of his brothers, as a form of reverse psychology.
The saying derives from the idea that cattle have thousands of hairs, and if you take one hair from one ox it would not be important, and one cattle even less important, and nine cattle, the hair is as insignificant and small as a molecule.
For a specific example, he remembers that he would take a cracker from his brother and then would brag about it, to make him feel his stupid his brother would state this fact that what his little brother accomplished was insignificant, therefore being uncool.
The idea of cattle can come from the idea that cattle are very important in Chinese culture, as a main source of food. The cattle being important, and the hair not, giving a contrast of importance. The action being thought to be important, but then again, not.