字符串分割为数组，并组合为mysql查询语句

$keyword = "hello word,你好世界";
$like = '';
preg_match_all('/./u',$keyword,$matches); //字符串分割为数组
foreach ($matches[0] as $ks=>$vs){
    if($like!=''){
        $like.= ' OR ';
    }
    $like .= " title like '%$vs%' ";
}