天空很大却看不清楚
[tiān kōng hĕn dà què kàn bù qīng chŭ]
This nickname conveys a sense of confusion or bewilderment despite being in an expansive or limitless situation. The 'sky' symbolizes endless opportunities, possibilities, and broad-mindedness while 'not seeing clearly' implies that one feels at a loss about which way to go or what to do among so many choices.