"Long ears" in Engpsh can be referred to as "long ears". It is a direct translation of the Chinese phrase "长耳朵".
As for its origin, the phrase is commonly used to describe a physical characteristic of certain animals, such as rabbits and elephants, that have elongated earlobes.
Example sentences in Engpsh with Chinese translation:
"The bunny has long ears that flop when he runs." (兔子有着长长的耳朵，跑起来耳朵摆动。)
"Elephants are known for their long ears and trunk." (大象以它们长长的耳朵和长长的鼻子而闻名。)