Could someone tell me how i can target a particular collapsible to add content in it?

I've a collapsibleSet including multiple collapsible in this format:

2. <div data-role=collapsible data-theme='c'
3.        data-collapsed-icon='carat-d'
4.        data-expanded-icon ='carat-u'
5.        data-collapsed=true
6.        data-iconpos='right'
7.        data-date =" + DateC  /* Content in format "2016-06-21"
8.        class='ui-corner-all ColDoc'>
9.        <h3>" + DateComplete + ")</h3>
10.        </div>

I would like to target the collapsible witch have the data-date === 'the date I'm looking for'