show leg的意思是“逃跑”，相当于run away（离开，逃跑、避）。

【例句】
When he tried to show leg, I got him by the neck.
当他想逃跑的时候，我一把将他抓住！

They show leg from the problem, hoping it will disappear of its own accord.
他们避开了这个问题，希望它不了了之。