Card bootstrap con colonne a 6

[Artgallery75]

Ho trovato questo codice bootstrap che farebbe al caso mio ma ha un problema si stringe se le colonne aumentano.
Io vorrei che dopo 6 colonne le altre andassero a capo.

Si può fare in qualche modo?

Devo integrare questo codice nel mio tema wordpress fatto da 0!

<div class="card-deck"> 
 
<div class="card">    
<img class="card-img-top" src="..." alt="Card image cap">    
<div class="card-body">      
<h5 class="card-title">Card title</h5>      
<p class="card-text">This is a wider card with supporting text below as a natural lead-in to additional content. This content is a little bit longer.</p>    
</div>    
<div class="card-footer">      
<small class="text-muted">Last updated 3 mins ago</small></div>  
</div>  

<div class="card">    
<img class="card-img-top" src="..." alt="Card image cap">    
<div class="card-body">      <h5 class="card-title">Card title</h5>      
<p class="card-text">This card has supporting text below as a natural lead-in to additional content.</p>    </div>    
<div class="card-footer">      
<small class="text-muted">Last updated 3 mins ago</small>    </div>  
</div>  

<div class="card"> 
<img class="card-img-top" src="..." alt="Card image cap">    
<div class="card-body">      
<h5 class="card-title">Card title</h5>      
<p class="card-text">This is a wider card with supporting text below as a natural lead-in to additional content. This card has even longer content than the first to show that equal height action.</p>    </div>  
  <div class="card-footer">      
<small class="text-muted">Last updated 3 mins ago</small>    
</div>  </div>

</div>