"Snow-white skin" 用英语可以说作 "porcelain skin"。
"Porcelain" 原本是指瓷器，因其白皙、坚硬、透明度高而被用来形容人类的皮肤。
例句：
She has porcelain skin that makes her look pke a doll. (她有雪白的皮肤，让她看起来像个娃娃。)
His porcelain skin was flawless and smooth. (他的雪白皮肤无瑕疵、光滑。)
I admire her porcelain skin, it's so beautiful. (我很喜欢她雪白的皮肤，它非常美丽。)