The combination of keys you have to use for it in our Lenovo K5 Note, are very similar to the default Android, but slightly different. This time, you have to press simultaneously, the Volume Down and Power buttons.
Once you're done, you'll hear the same sound you hear when you take a picture. That means the screen of your terminal already be captured as an image, so you can go to the gallery to find it and do with it what you want.