How to add new domain tld to domain list?
If you want to add more tld by yourself. Please follow this step to make it.
1. go to link http://www.iana.org/whois then try find a domain (eg: duongca.tech) you want add to find whois server in whois info.
2. Add tld to server list and shortcode then try to check a domain
3. Click to view domain result whois you'll see text to check domain available or unavailable
4. Copy this text and change old value on domain list in file \wp-content\plugins\iw_composer_addons\inc\whois.servers.json