I was facing the same issue; and the following worked well for me.
<div class="row">
<div class="col-md-6">
<div class="col-md-12">
Some Content..
</div>
</div>
<div class="col-md-6">
<div class="col-md-12">
Some Second Content..
</div>
</div>
</div>
This will automatically render some space between the 2 divs.