Since the Card display a single value, so even though your query may return a series of data, it will take the first value.

One question: So let say if possible that value received array of number. How would you want those number to be display on the card.

I ask this question because I would like to see how you would like to display using card. If you could provide a drawing, or explanation of use case, that's would be great!

I think it is matter of design and css only. You can make a card by yourself and fill it with your own data. Let say you have a dataStore, each rows contains film name, director and year, you can do like this to list all information:

<?php foreach($this->dataStore("film") as $row):?>
<div class="card" style="width: 18rem;">
  <img class="card-img-top" src="<?php echo $row["film_image_url"]; ?>" alt="Card image cap">
  <div class="card-body">
    <h5 class="card-title"><?php echo $row["title"] ?></h5>
    <p class="card-text"><?php echo $row["description"] ?></p>
    <p class="card-text"><?php echo $row["director"] ?></p>
    <p class="card-text"><?php echo $row["year"] ?></p>    
  </div>
</div>
<?php endforeach; ?>

Here is more info about the Bootstrap Card.

Hope that helps.

You are welcome :)