当输入变量超过1个字符时，为什么我得不到任何结果？

So this is supposed to be a search field for songs. When i search for a single character like "o" for example, the result is songs with the letter "o" in any position. When i search for more than one character like "oo" for example, i don't get any results at all, even though i got songs with "oo" in the title.

<?php
include 'conn.php';

if (isset($_POST['submitsearch'])){
    $search=$_POST['search'];
    $query2 = "select * from songs where Title LIKE '%".$search."%'";

    $result2 = mysqli_query($connection, $query2);

    $row = mysqli_fetch_array($result2, MYSQLI_ASSOC);
    while($row = mysqli_fetch_array($result2, MYSQLI_ASSOC)){
      echo $row['Title'];
    }
}

Possibly you only have one row with a oo in it. Your code will always loose the first row of the results set as you have a fetch OutSide the while loop.

Try without that like this

<?php
include 'conn.php';

if (isset($_POST['submitsearch'])){
    $search=$_POST['search'];
    $query2 = "select * from songs where Title LIKE '%".$search."%'";

    $result2 = mysqli_query($connection, $query2);

    // gets first row and then does nothing with it
    //$row = mysqli_fetch_array($result2, MYSQLI_ASSOC);
    while($row = mysqli_fetch_array($result2, MYSQLI_ASSOC)){
      echo $row['Title'];
    }
}

You should also know that your script is at risk of SQL Injection Attack Even if you are escaping inputs, its not safe! Use prepared parameterized statements