JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="hello"> 
    <li>with multiple classes.</li>
    <li class="hello"> and</li>
    <li class="aetw"> and</li>
    <li class="hello"> I want to hide every </li> 
    <li class="sdf"> and</li>
    <li class="hello"> I want to hide every </li> 
</ul>

CSS

ul.hello>li:not(.hello){
    display : block;
    border:1px solid grey;
}
ul.hello>li.hello{
    display : block;
    border:1px solid red;
}