nf_handsome

here is something else I tried... give it ahot and not the change in your second div

<div style="display:block; margin:auto;">
<script src="https://fast.wistia.com/embed/medias/hl78wc0g3o.jsonp" async></script>
  <script src="https://fast.wistia.com/assets/external/E-v1.js" async></script>
  <div class="wistia_responsive_padding">
  <div class="wistia_responsive_wrapper" style="height:35%;left:35%;position:absolute;top:0;width:35%;">
  <div class="wistia_embed wistia_async_hl78wc0g3o videoFoam=true"</div></div></div>
  
  </div>

33.33% would be just near it. Good luck

We may need to see the contents of each div you are using. in you last div you have width as 100%. this makes the entire width of the video to take the entire width of your screen...
On second thought...
Play around with the div I placed around your codes: Perhaps not the best fix but may lead you to the right fix.
Good luck

<div style="display-box;margin-left:750px;">

  <script src="https://fast.wistia.com/embed/medias/hl78wc0g3o.jsonp" async></script><script src="https://fast.wistia.com/assets/external/E-v1.js" async></script><div class="wistia_responsive_padding" style="padding:60% 0 0 0;position:relative;"><div class="wistia_responsive_wrapper" style="height:35%;left:0;position:absolute;top:0;width:35%;"><div class="wistia_embed wistia_async_hl78wc0g3o videoFoam=true" style="height:100%;position:relative;width:100%;">&nbsp;</div></div></div>

</div>

Thanks... That's an option....
but somehow I still have to learn all the Bootstrap's classes and I am confined to all those names and have to remember what they do and their effects.
I can make my own CSS3 classes and build my own Framework and see it grows slowly...
But I see, it boils down to:  if I use Bootstrap I have to learn its encyclopedia of classes.

If I don't know Bootstrap classes and what they are doing, their effects etc.etc. then bootstrap is useless to me...
To make Bootstrap useful, I have to learn Bootstraps compleet encyclopedia classes.
I won't say that I am advanced in HTML5 and CSS3. (leaving JS/JQ outside for now).
Wouldn't it be better for me to build my own bootstrap with my own customised design and develop it as I go along... in this way I know my own code and can adjust/update where en when I want without having to dive into Bootstraps encyclopedia of classes.
Am I seeing thinking wrong on this?
Thanks for your input to make me see it from another point of view