Bootstrap: two column centered

Add a container, remove the center div and add two blank col-lg-2 on either side so it adds up to 12 columns:

<div class="container">
 <div class="row">
  <div class="col-lg-2">
  </div>
  <div class="col-lg-3 gauche">
  Left div
  </div>

  <div class="col-lg-5 corps">
  Right div
  </div>
  <div class="col-lg-2">
  </div>
 </div>
</div>

You would want to use a column offset class. If you are using a stock build of Bootstrap all of the column classes need to add up to 12. Your col-lg-3 and col-lg-5 only add up to 8 so adding a col-lg-offset-2 should fix you up to center. Also, bootstrap has a built in centering class container i personally would use that. See below code:

<div class="container">
<div class="row">

    <div class="col-lg-3 col-lg-offset-2 gauche">
    Left div
    </div>

    <div class="col-lg-5 corps">
    Right div
    </div>

</div>
</div>