It sounds like you may have zoomed in on you’re current website and have not specified how the div’s should act as of yet.
<div class="col-xs-12"> //Stuff here etc </div>
The above div will display well across all sizes, but obviously you should assign all screen sizes (xs, sm, md and lg). If you could update you’re question with more information that would help greatly.
solved My Bootstrap Window Became to large?