in my lenovo P11 tablet:
switch to PRODUCTIVITY MODE which in settings,
then in the App list I found all the missing App, I drag it the home screen, then I exit the productive mode, the App is now appeared.
ENABLE PRODUCTIVITY MODE: From the home screen, swipe down from the Notification bar then select the Settings icon. Scroll to and select Productivity Interface. Select the Productivity Interface switch On. A Navigation bar will appear on the bottom of the screen that will allow you to easily switch between apps
