<div>John Resig</div>
<div>George Martin</div>
<div>Malcom John Sinclair</div>
<div>J. Ohn</div>

{
  const ex = $('div:contains(John)')
  
  console.log(ex)
}

{
  const ex = Array.from(document.querySelectorAll('div')).filter(element => {
    return element.textContent.includes('John')
  })
  
  console.log(ex)
}