JSFiddle - React, Tailwind, and code Playground
HTML
<p class="threadNametd"><span>Hello</span>, how are you?</p>
<p class="threadNametd">Me? I'm <span><b>good</b></span>.</p>
JavaScript
var filtered = $('.threadNametd');
filtered.each(function() {
var there_is_no_b = $(this).find('b').length === 0,
html = $(this).html();
if (there_is_no_b) {
//Do something
console.log(html);
} else {
console.log(html + ' <-- "b" here');
}
});