JSFiddle - React, Tailwind, and code Playground

HTML

<div class="two-columns some-other-class">
    <div class="not-to-be-selected"></div>
    <div class="two-columns another-class"></div>
    <div class="two-columns third-class"></div>
</div>

JavaScript

$.extend($.expr[':'], {
    classEndsWith: function (elem, index, match) {
        var found = false
        var classes = elem.className.toLowerCase().split(' ');
        var suffix = match[3].toLowerCase();
        $.each(classes, function (i, c) {
            // Check if className ends with value in suffix
            if (c.indexOf(suffix, c.length - suffix.length) !== -1) {
                found = true;
                return false;
            }
        });
        return found;
    }
});
var e = $('div:classEndsWith(columns) div:classEndsWith(columns)');

$.each(e, function (i, val) {
    alert($(val).attr('class'));
});