Can't resolve some domians

[abuamaar amaar]

**Dear Bind Users
Our Recursive & Open DNS Bind 9.2.4 (Solaris 10, Linux) & Bind
8.2.4(Soalris 8) can't reslove the below domians

ims-oman.com
sinjincorp.co.kr

connection timed out; no servers could be reached

but when I use dig +norec or dig +trace ims-oman.com / sinjincorp.co.kr it
can reslove

and when I check other DNS such as OpenDNS (208.67.222.222) it can
be resloved

The above domains are reachable from other countries and it is not block by
the ISP here

How I can solve this issue?

Thanks in advance


Best Regards
Yassir