PHP CURL isn't processing encoded return data properly

set another curl option for CURLOPT_ENCODING and set it to "" to ensure it will not return any garbage

   curl_setopt($ch, CURLOPT_ENCODING ,"");

You Can use header

   header('Content-type: text/html; charset=UTF-8');

and after decode string

 $page = utf8_decode(curl_exec($ch));

It's worked for me

or

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_ENCODING, 'UTF-8');
curl_setopt($ch,CURLOPT_USERAGENT,'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13');

after add this

$page = curl_exec($ch);
$dom = new DOMDocument('1.0', 'utf-8');
libxml_use_internal_errors(true);
@$dom->loadHTML(mb_convert_encoding($page, 'HTML-ENTITIES', 'UTF-8'));