Select matching words from two texts

This function returns matching words array from two texts or returns false in case of not matching any words.

<?php
function strings_intersect_words($str1,$str2){
$str1 = trim($str1);
$str2 = trim($str2);

$str1_words = explode(" ",$str1);
$str2_words = explode(" ",$str2);

$str1_words = array_unique($str1_words);
$str2_words = array_unique($str2_words);

$intersect_words = array();

foreach($str1_words as $str1_word){
if(array_search($str1_word,$str2_words)!==false && trim($str1_word)!=""){
$intersect_words[] = $str1_word;
}
}

if(empty($intersect_words)){
return false;
}

return $intersect_words;
}

$str1 = "I am Ruben Sargsyan from Armenia. I am a web developer.";
$str2 = "http://rubensargsyan.com is a web developer Ruben Sargsyan's personal website.";

$intersect_words = strings_intersect_words($str1,$str2);

print_r($intersect_words);
?>

Output:

Array ( [0] => Ruben [1] => a [2] => web )