Display part of st.checkbox

In my dataset there are 50 dealers and we want to know the total sales of the selected dealers. So I put all the dealers into the checkbox using st.checkbox but it looks so clumsy in the interface. Now I want to add scroll option into the checkbox so that I can scroll down and select the dealers accordingly. If the above question is not clear for you then I attach two pictures. 1st picture

which I have now and 2nd picture
which I want to do. In 2nd picture it is clearly shown that there is a scroll option in left hand side. I will be grateful if anyone give me a solution.

Can anyone please answer this question?