donkeys' lips don't match horses' jaws —beside the point; incongruous; farfetched; irrelevant;neither here nor there ❍ 陈正公听了这些话，～，急了一身的臭汗。(《儒林外史》 594) The horse's mouth didn't fit the donkey's head—this story didn't tally with Whiskers Mao's! Chen broke into a cold sweat.
驴唇不对马嘴lü chun bu dui ma zui
donkeys’ lips don’t match horses' jaws—incongruous
驴唇不对马嘴lǘ chún bù duì mǎ zuǐ
比喻答非所问，或事物不相合。irrelevant, out in left field, an answer beside the point, farfetched