In this case, that won't help, because `.box` is already a TLD and `fritz.box` has been registered by someone. Compare these two, the first is from my laptop connected to a Fritz!Box, the 2nd. one is from a server that's not connected to any sort of Fritz!Box:
Expected result, resolved by the box itself:
$ host fritz.box.
fritz.box has address 192.168.178.1
fritz.box has IPv6 address fd00::e72:74ff:fece:6656
fritz.box has IPv6 address 2a02:908:616:a8c0:e72:74ff:fece:6656
Result if for some reason, DNS resolution fails on the box (e.g. you're not connected to your own network, someone disabled the resolver on the box, someone configured a non-box DNS on your machine):
$ host fritz.box.
fritz.box has address 45.76.93.104
fritz.box has IPv6 address 2001:19f0:6c00:1b0e:5400:4ff:fecd:7828
Your query results make sense, since the Fritz!Box is authoritative for the (local) .box tld. Try again with google.com and google.com. If you're using Windows, it should append .fritz.box to the former, which is the issue here.
Expected result, resolved by the box itself:
Result if for some reason, DNS resolution fails on the box (e.g. you're not connected to your own network, someone disabled the resolver on the box, someone configured a non-box DNS on your machine):