<?php

$chars = "\u1006\u1092\u1019\u1021\u102c\u101b\u1036\u102f \u1019\u1002\u1062\u1007\u1004\u1039\u1038 (\u1042\u1040\u1041\u1046 \u1007\u1030\u101c\u102d\u102f\u1004\u1039)";
$encoding = ini_get('mbstring.internal_encoding');
$str = preg_replace_callback('/\\\\u([0-9a-fA-F]{4})/u', function($match) use ($encoding) {
        return mb_convert_encoding(pack('H*', $match[1]), $encoding, 'UTF-16BE');
    }, $chars);
echo $str;