Display filter in form
ip.src_host eq my.host.name.com yields no matching packets, but there is traffic to and from this host.
DNS name is resolved successfully, and filters using ip addresses like
ip.src eq 184.108.40.206 work as expected.
The problem might be that Wireshark does not resolve IP addresses to host names and presence of host name filter does not enable this resolution automatically.
To make host name filter work enable DNS resolution in settings. To do so go to menu "View > Name Resolution" And enable necessary options "Resolve * Addresses" (or just enable all of them if not sure :).