Did you really whiten the yellow toothbrush with toothpaste?
I don't think it is necessary to use any particularly good whitening toothpaste to whiten teeth. Even a good and expensive toothpaste may not be able to whiten teeth. The most important thing is to brush your teeth scientifically-brush it up and down with a toothbrush, and don't put it in your mouth and brush it sideways desperately. This is a bad way to brush your teeth. Trust me, try for a while and make sure you will find something unexpected! ! This is how I whiten my teeth, and so are my friends around me! !