Check if a string contain multiple specific words

How to check, if a string contain multiple specific words?

I can check single words using following code:

$data = "text text text text text text text bad text text naughty";
if (strpos($data, 'bad') !== false) {
    echo 'true';
}

But, I want to add more words to check. Something like this:

$data = "text text text text text text text bad text text naughty";
if (strpos($data, 'bad || naughty') !== false) {
    echo 'true';
}
?>

(if any of these words is found then it should return true)

But, above code does not work correctly. Any idea, what I'm doing wrong?