Dunno if this is the right place to share this or not and also i dunno if this is a repost or not, mod you know what to do if this thread located at the wrong place/repost
So here's how to do it :
First, open an APK with 7zip/winrar. My example here is BOMBSHELLS HELL'S BELLES v1.0.1 APK.
Once you open it, go to package -> res -> raw -> open properties.dat with notepad
and you will find this
Copy the obb_base_url link and obb_main_filename, so it will look like :
Copy paste to your favourite browser or directly to IDM, and start download
credit @ Rakesh Bro