[JohnWoo]

Yes.. You are right msimplay. I missed that thing.
Uploading updated zip and to upgrage just change in search.php

//fast list of forums visible and searchable for user
	foreach ($bbuserinfo['forumpermissions'] AS $forumid => $fperms) {
		if (!($fperms & CANVIEW) OR !($fperms & CANSEARCH) OR !verify_forum_password($forumid, $forum['password'], false)) {
			$not_forumid .= $forumid." ";
		}
	}

to

//fast list of forums not visible or searchable for user
	foreach ($bbuserinfo['forumpermissions'] AS $forumid => $fperms) {
		if (!($fperms & CANVIEW) OR !($fperms & CANSEARCH) OR !verify_forum_password($forumid, $forum['password'], false) OR !($forumcache[$forumid]["options"] & $_FORUMOPTIONS["indexposts"])) {
			$not_forumid .= $forumid." ";
		}
	}