Q:

Add slight gap in paragraph

I understand how padding works but is there a chance and how can I add a slight gap inside p between new text lines. 
Here is a JSFIDDLE.

<script src="https://code.jquery.com/jquery-2.2.4.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet" />
<div class="col-md-4">
  <h2 class="text-center">Heading</h2>
  <p class="text-center">Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod.Donec sed odio dui.Donec id elit non mi
    porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.Donec id elit non mi porta gravida at
    eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.</p>
  <p><a class="btn btn-default" href="#" role="button">View details &raquo;</a>
  </p>
</div>

A:

You can increase the height of each line by setting the line-height property for the <p> element, for example:

p {
  font-size: 1em;
  line-height: 2em;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet" />
<div class="col-md-4">
  <h2 class="text-center">Heading</h2>
  <p class="text-center">Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod.Donec sed odio dui.Donec id elit non mi
    porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.Donec id elit non mi porta gravida at
    eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.</p>
  <p><a class="btn btn-default" href="#" role="button">View details &raquo;</a>
  </p>
</div>

To increase space between the descending characters of the previous line and the ascending portions of the subsequent line simply ensure that the line-height property is greater than the font-size property. Although you don't have to specify the units for the line-height, for example:

p {
  font-size: 1em;
  line-height: 2;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet" />
<div class="col-md-4">
  <h2 class="text-center">Heading</h2>
  <p class="text-center">Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod.Donec sed odio dui.Donec id elit non mi
    porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.Donec id elit non mi porta gravida at
    eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui.</p>
  <p><a class="btn btn-default" href="#" role="button">View details &raquo;</a>
  </p>
</div>

In which case the line-height property acts as a multiplier, rather than as a specific length.

