JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="container">
    <li data-media-tv="bar"></li>
    <li data-media-dvd="baz"></li>
    <li data-media-bluray="cat"></li>
</ul>

JavaScript

var container = document.body.getElement('.container');

// Iterate through all li elements in the container
var matches = container.getElements('li').filter(function(li) {
    var numAttr = li.attributes.length;
    for(x=0;x<numAttr;x++) {
        var attr = li.attributes[x];
        return attr['name'].test('data-media-(tv|dvd)');
    }
});

console.log(matches);