Apagar uma div especifica

if (document.getElementsByTagName("div")[4].innerHTML.indexOf('Um texto qq')!=-1)
{
var div0 = document.getElementsByTagName('div')[4];
/*apaga a div*/div0.style.display='none';
//location.href = window.location;
}


//----------------------------------------------------------------------
if (document.body.innerHTML.search('um texto')<1200)
{
location.href = window.location;
}