a deed as tiny as hair
Si FA Zhi Gong, a Chinese idiom, Pinyin is s ī f à zh ī g ō ng, which means minor credit. It comes from the ten annals of Shang Han Dynasty by Cai Yong of Han Dynasty.
The origin of Idioms
Cai Bozhe's ten annals of the upper Han Dynasty: "father and son are both favored, so they can't lose heart and make contributions to the silk."
Idiom explanation
Little credit.
a deed as tiny as hair
make up deficits and increase surpluses - niǔ kuī zēng yíng
horses and oxen kept in the same stable - niú jì tóng zào