To see something clearly but be unable to obtain or grasp it; an illusion or an unattainable goal, like flowers in a mirror.
他多年来一直追求那个看似完美的梦想，最终才发现那不过是镜里采花，根本无法实现。
For years, he pursued that seemingly perfect dream, only to realize in the end that it was merely like picking flowers in a mirror, utterly impossible to achieve.
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