Why my notifications won't show on lock screen?

[Hasi Jb]

I have a UTOK 351D with 4.2.2 android on it, and i have a "show notifications on lock screen" option in settings->display, but it doesn't work. I've also set all my apps to show the notifications on lock screen but nothing happens, they only show in the status bar. The phone isn't rooted, it's stock, and with other lock screens apps like cm locker, the notifications thing works, but that kind of app are draining my battery really fast because it's just a 1200 mAh battery...
So what can I do to show me the notifications on lock screen with the stock lock screen?