JSFiddle - React, Tailwind, and code Playground

HTML

<div class="classOne">
    <div class="classTwo">
        <div class="classThree">
            test
        </div>
    </div>
</div>

JavaScript

var klass = "classOne classTwo classThree";
var arr   = klass.split(/\s+/);
var sel   = '.' + arr.join(' .');

console.log( $(sel).text() );