Ambient Display can also be, wake screen to show notifications, lift to check phone and any screen gesture that works with the screen off.
Remember to check digital wellbeing as well because sometimes, battery stats forgets to include apps even if they have had significant usage.
Lets take the stats above as an example. If AOD is active and the true screen time really is 2h 14min, then Ambient display should say about 7h. Based on the battery drain it's likely that the real screen time was more than 3h. Then it's starting to look more normal. The AOD feature also consumes quite a lot of battery in my opinion. It's one of the first things you should turn off (if it's on) if you want better battery.
Here are some general battery saving tips
1. restart your device more often. It solves more issues than you would think.
2. go to system settings -> battery -> powermaster -> auto-start manager and prevent all the apps to auto start that you don't need a notification from.
3. Go to display settings and disable every option under Standby screen and switch to Auto refresh rate if you have this option
4. Go to system settings -> advanced -> Mobile Manager -> Memory cleaner -> Turn on Super Clean mode -> enter app list and uncheck any app that you must get notifications from -> go back -> open recent apps overview and press clear all.
Restart your phone.
Sometimes it's something on your cellular or wifi network that's causing your drain. To test this, put your phone in flight mode (mobile data, wifi & BT off) before you go to bed. Do not plug in your charger. If you have lost 1% or more of battery per hour of sleep, then there might be a bug in the system that we have to investigate.
You may also check out general battery saving tips like these
https://uk.pcmag.com/how-to/9960/9-tips-to-boost-your-android-phones-battery-lifeTips for battery charging and storage
https://www.asus.com/US/support/FAQ/1009546