JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.14.0/jquery.validate.js"></script>
<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.14.0/additional-methods.js"></script>
<form id="demo-form">
    <input type="text" name="product[0]" id="p1" />
	<br/>
    <input type="text" name="product[1]" id="p2" />
	<br/>
    <input type="text" name="product[2]" id="p3" />
    <br/>
	<input type="text" name="product[3]" id="p4" />
    <br/>
	<input type="submit" value="submit" />
</form>

JavaScript

$(document).ready(function() {

    jQuery("#demo-form").validate({
        // other rules & options
		groups: {
		    myproducts: "product[0] product[1] product[2] product[3]"
		}
    });
    
    // assign the rule to all field names that start with 'product'
    jQuery('[name^="product"]').each(function() {
        jQuery(this).rules('add', {
            require_from_group: [2, jQuery('[name^="product"]')]
        });
    });

});