.find() method allows us to search through the descendants of these elements in the DOM tree and construct a new jQuery object from the matching elements.
HTML
<div class="parent">
<div class="children" name="first">
<ul>
<li>A1</li>
<li>A2</li>
<li>A3</li>
</ul>
</div>
<div class="children" name="second">
<ul>
<li>B1</li>
<li>B2</li>
<li>B3</li>
</ul>
</div>
</div>
jQuery
$('.parent').find('.children[name="second"] ul li').css('font-weight','bold');
Output