   <span class="input-group-prepend">
                    <button type="button" class="btn btn-primary"><i class="fa fa-facebook"></i></button>
                  </span>
                  <input type="text" id="input3-group2" name="input3-group2" class="form-control" placeholder="Search">
                  <span class="input-group-append">
                    <button type="button" class="btn btn-primary"><i class="fa fa-twitter"></i></button>
                  </span>
                </div>
              </