They both laughed, because to snatch sth from under someone's nose is to take or steal sth directly in front of someone.

假如我告诉你他们在哪里，你可能会从我鼻子底下把他们抢走。

Tall old assume sth as a matter of course the ground thinks uncle can marry him, hear uncle order rule in person however sweet plain take-over happy forest.

高老大想当然地以为老伯会娶自己，却亲闻老伯命律香川接管快活林。