UTF-8 characters don't display correctly

Question

This is my PHP code:

<?php
$result = '';
$str = 'Тугайный соловей';
for ($y=0; $y < strlen($str); $y++) {
    $tmp = mb_substr($str, $y, 1);
    $result = $result . $tmp;
}
echo 'result = ' . $result;

The output is:

Тугайный Ñоловей

What can I do? I have to put $result into a MySQL database.

Answer 1

Just add this line at the beginning, after the connection with server:

mysqli_set_charset($conn,"utf8");