what more do you want - jam on it? idiom UK informal
知足常乐（用来表示某人应对其所拥有的或别人所提供的表示感激，而不应当得寸进尺）
used to say that someone should be grateful for what they have or have been offered, and not demand something better
They've given him a holiday in Italy. What more does he want - jam on it? 他们已经让他到意大利度假。他还想要什么呢？知足吧！