JSFiddle - React, Tailwind, and code Playground

HTML

<div id='sheet'>
    <div class='item' id='field-18583'>This is yet another test</div>
    <div class='item' id='field-18585'>This is test data</div>
</div>
<input type="text" id="t" /><button id="s" onclick="searchIt()">Search</button>

CSS

span { background:yellow; }

JavaScript

var sheet,
    searchIt = function() {
        var v = document.getElementById('t').value;
        
        sheet = (typeof sheet == "undefined") ?
                document.getElementById('sheet').innerHTML :
                sheet;

        document.getElementById('sheet').innerHTML = 
            sheet.replace(new RegExp(v, 'ig'), "<span>$&</span>");
    };