if you previously bought tokens elsewhere when you login to the truswallet with the same key code BSC then your old tokens will enter because they are connected together
just to be clear, by 'enter', i think he meant shows on your token list. a wallet doesn't 'store' your tokens, your tokens are on the blockchain. if your token doesn't show up on your wallet then you can easily add a custom one. don't get tricked if there's an offer claiming that you can access some secret token using X wallet or something, especially if they need you to input your seed.