此地无银三百两（此地無銀三百兩）　

◎ 此地无银三百两 cǐdì wú yín sānbǎi liǎng

[no 300 taels of silver buried here—a guilty person gives himself away by conspicuously protesting his innocence] 比喻本想隐藏、掩饰,结果反而暴露