Direct translation could be: "I am quite stubborn, if I am in a temper, one can't pull me back even using 9 cows." 9 cows --> really a lot of effort.... it means .... very difficult to change his mind.

我来补充听说读写，除了数量使用不同外，还可以使用不同的动物，比如马啊，骡子啊。 我的理解是，动物们的力气很大，都拉不回来。

‘9头牛都拉不回来’This is a metaphor.you know the cows are very strong.it means that no one can change his decided

牛因為執性強烈 所以被用作農耕動力 又因其執性 故引申為固執 倔強之意 作形容詞用 如「牛脾氣」「牛性子」 紅樓夢第十七回「眾人見寶玉牛心，都怪他獃痴不改。」 試想 脾氣無形 牛能拉得回來嗎 「九頭牛都拉不回來」是把「牛脾氣」 該詞的引申意義再度轉化為具體形象 至於 三頭 八頭 九頭 十頭 都有人用 但已非所問

Means one-track mind. Difficult to change one's mind.