MySQL全文搜索无法正常工作

Question

I have this table with song titles, artist etc.

---

| id | artist | title | search_tags |

if(isset($_POST["search_value"]) && $_POST["search_value"] != null) {
        $search_value = $db->mysqli->real_escape_string($_POST["search_value"]);

        //hiq apostrofet
        //hiq pikat
        $search = array("\'", ".", " ");
        $replace = array("", "", " +");
        $search_value = str_replace($search, $replace, $search_value);

        $query = "
            select * from `music` 
            where 
                match(`search_tags`) against ('+$search_value*' IN BOOLEAN MODE)
            order by views desc
            limit 1
        ";

        //+ vihet per t paren

        $run_query = $db->mysqli->query($query);
        $result = $run_query->fetch_assoc();

        if($run_query->num_rows > 0)
            echo json_encode($result);
    }

It works fine in most cases but it is not working for some others.

Two main problems are:

1. If I have two songs with these search tags:

a) era isterfi money per money

b) era istrefi e dehun

and when I search using this query: era e dehun it shows me era istrefi money per money as a result. Why is this happening? Are single chars a problem?

And 2. If I have a song with search_tags: 23 miley cyrus and I use 23 as a search query it shows me no result. Everything work fine if I search Miley for ex.