- stristr: documentation ( source)
- str_replace: documentation ( source)
<?php
$query = "Google";
$elasticaResult = array("content"=>"Google Account, you need to have JavaScript enabled in your browser. Refresh this page after you have enabled JavaScript. Create a new Google Account Name First name First Last name Last");
$queryReplace = "<span class=\"found\">".$query."</span>";
$descriptionContent = $elasticaResult->content;
$foundQuery = stristr($descriptionContent, $query);
$queryInDescription = str_replace($query, $queryReplace, $foundQuery);
echo $queryInDescription;