Sometimes you need to check which glue records are used on domain and where they are pointed
First you should check which nameserver is responding for this tld. For example if we wanna check .com domain we need to ask proper nameserver
dig +short com. NS
e.gtld-servers.net.
k.gtld-servers.net.
j.gtld-servers.net.
h.gtld-servers.net.
m.gtld-servers.net.
a.gtld-servers.net.
l.gtld-servers.net.
i.gtld-servers.net.
g.gtld-servers.net.
c.gtld-servers.net.
d.gtld-servers.net.
f.gtld-servers.net.
b.gtld-servers.net.
We can chose some random dns server from them and execute
dig +norec @b.gtld-servers.net. example.com. NS
Then we will get which nameservers on which ip are responding for this domain