Add enough liquid dish soap to the jar to cover the bottom. Fill half of the jar with warm water and stir to mix.  Any liquid dish soap will work, regardless of how mild it is or what additional chemicals it may contain. The right size container will depend on how many stink bugs you intend to capture. A small custard cup or ramekin is enough if you only plan on killing a few of the pests, but a larger jar or small bucket should be used if you plan on taking care of a major infestation all at once. When you come across a stink bug, flick it off its post with a popsicle stick or chopstick and down into the soapy solution.  Work quickly. Some species of stink bugs can fly and may escape if you do not manage to flick it off in one fell swoop. Stink bugs should drown within 20 to 40 seconds. The bugs breathe through pores beneath their waxy exterior shells, and when soap plugs these pores up, the bugs suffocate. You could also wear disposable gloves and pick up the stink bugs by hand. Similarly, you could pick them up with tweezers. Picking them up directly ensures that they will not be able to escape, but they may release their odor if you do not work quickly. After you collect a few stink bugs in your soapy water, flush the contents of the jar down the toilet to dispose of the bugs and the dirty water. Wait until you collect a few stink bugs instead of flushing them individually in order to save water.

TL;DR in Vietnamese:
Rót xà phòng rửa bát và nước vào lọ. Đập cho bọ xít rơi vào lọ. Giội nước cho trôi xác bọ xít.