How can I access cache files of an app? I have a marshmallow device, it has custom ROM, and is obviously rooted.

I am looking for a way to access the app data, cache of other apps. As I am rooted, I guess this is possible.

I tried searching and found that Titanium Backup can access databases and cache files.

I am only able to save databases but not all the cache files.

So, is there any app to get all the cache files saved?
Most apps store their cache data, files in the /data/data/ directory.

Starting from root directory "/".

For more detailed explanation, see @Izzy Comment.