Apex domains cannot have CNAME records.
Question and response
Question
dig tvujweb.com. NS
Answer
tvujweb.com. 3 NS ns.tvujweb.com.
tvujweb.com. 3 NS ns.tvujweb.cz.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0