How do I boost the sound on my portable DVD player?

if u want your sound to go up on your portable then what u have to do is normally look at the left hand side or it can be on the right hand side and there will be this bumpy thing that u put your finger on it and move the bumpy thing and there the sound is up and u can watch something with sound if u want your sound to go up on your portable then what u have to do is normally look at the left hand side or it can be on the right hand side and there will be this bumpy thing that u put your finger on it and move the bumpy thing and there the sound is up and u can watch something with sound if u want your sound to go up on your portable then what u have to do is normally look at the left hand side or it can be on the right hand side and there will be this bumpy thing that u put your finger on it and move the bumpy thing and there the sound is up and u can watch something with sound