What is the Php function to search for a list of words in a text and if one of the words matches then return true.

So say we want to search for these words:
$words = array('wag', 'dog', 'tail');

for ($i=0, $i<count(documents), ++$i) {

$documnt = documents[$i];

if (find_words($words, $document)) {

$match[$i] = 'yes';



so is there a Php function that would do what find_words() is doing
in above sample code?