Parallax: how to make text scroll at different speed than bg

Hello, I have a basic parallax working similar to your demo, what I'm trying to figure out now is how can I make the text on top of a background image scroll at a different speed than the background? 

For example, using some code from your demo, how would I make each text scroll at different speeds?

<div class="view jarallax" style="height: 100vh;">
      <img class="jarallax-img" src="https://mdbcdn.b-cdn.net/img/Photos/Others/img%20%2844%29.jpg" alt="">
      <div class="mask rgba-blue-slight">
        <div class="container flex-center text-center">
          <div class="row mt-5">
            <div class="col-md-12 col-xl-8 mx-auto wow fadeIn">
              <h1 class="display-3 font-weight-bold mb-2 wow fadeInDown" data-wow-delay="0.3s">I want this to scroll fast over the background image</h1>
              <h1 class="display-3 font-weight-bold mb-2 wow fadeInDown" data-wow-delay="0.3s">This text should scroll slower over the background image</h1>
            </div>
          </div>
        </div>
      </div>
    </div>