Having trouble isolating " voice " and background music

There this video called : Bodybuilding Twins, The Harrison Twins, on youtube, and i am trying to isolate the voices out of the background music. The person who made the video does not know the name of the song. All he mentioned was something about royalty free.
I tried all of the tutorials on audacity tutorials but none of it works… I am new to audio editing. Please give me advice and tips on how to deal with this. Thank you.

I started by recording the sound of the video using freecorder. Then import it to audacity

Then it probably can’t be done (sorry :frowning:)
There are some suggestions here about how to go about the task, but note that it stresses that in many cases it is not possible to separate vocals from background music. http://wiki.audacityteam.org/wiki/Vocal_Removal