JSFiddle - React, Tailwind, and code Playground

HTML

<div id="f">
  <select name="name_ob" size="6">
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
  </select>
  <input type="text" name="opt" id="text">
</div>

JavaScript

const opt = document.querySelectorAll('option');
document.querySelector('#text').addEventListener('input', ({
  target
}) => {
  let searsh = [];
  if (target.value) {
    searsh = [...opt].filter(i => i.value.includes(target.value)).map(e => e.value)
  }
  console.log(searsh)
}, false)