Surprised that your Search attempt came up with nada. It sounds like you are not using it properly. Try the 2nd field instead of the first or try to figure out how to use the Advanced Search. A slice can refer to any shot where the shuttle is cut, chopped or brushed in order to make it tumble or, often, to cause it to spin faster. In either case, the trajectory (and often the speed) of the shuttle is affected. Here is one example: badminton.tv/content/item/doubles-net-play-technique/106.html ...
It appears than Badminton.TV has changed the access to their "free" videos. They now require registering to access all videos & other materials on their web site. However, they are currently offering a Free one month trial. The link I provided in the previous post now needs a username (& password). Also try the instruction video below for a discussion on slicing: youtube.com/watch?v=YrVzEFvhPno