JSFiddle - React, Tailwind, and code Playground

HTML

<div class='row-father'>
       <legend> Title here </legend>
        <div class="row-fluid">1</div>
        <div class="row-fluid">2</div>
        <hr/>
        <div class="row-fluid">3</div>
        <div class="row-fluid">4</div>
        <div class="row-fluid">5</div>
        <div class="row-fluid">6</div>
        <hr/>
        <div class="row-fluid">7</div>
        <div class="row-fluid">8</div>
        <hr/>
    </div>

JavaScript

$('.row-father').find('hr').eq(1).prevAll('.row-fluid').hide();