一叶障目

unable to see the wood for the trees; fig. only able to see isolated details, and not the bigger picture

lit. to see a leopard through a narrow tube (idiom); fig. to miss the big picture

lit. not to know the true face of Lushan Mountain (idiom); fig. can't see the forest for the trees

lit. the eye cannot see the eyelashes (idiom); fig. unable to see one's own faults; to lack self-awareness

lit. see one spot on a leopard (idiom); fig. a restricted view

multitude of blind people touch an elephant (idiom, from Nirvana sutra 大般涅盘经); fig. unable to see the big picture; to mistake the part for the whole