Open ES File Explorer and click...
(3 vertical dots) > Settings > Root settings
Staring at the bottom uncheck the bottom 3 boxes,
Leave the next box, Up to Root, checked.
and then uncheck the top box.
Back out of ES File Explorer
While you were doing that you may have had the program asking for super user access. If so, you may also have noticed that even if you picked deny access the program was granted super user privileges anyway. Even the most careless of system administrators only grant themselves super user access long enough to accomplish the task at hand, and then they turn super user access back off. Unchecking all but Up to Root will allow you to see your entire file structure without the risk of accidentally erasing something vital, and turning your tablet into a paper weight.