Basic search in Host or Content Hosts shows more hits than expected

On 3.2/4.4 and when I type in a text string in the search field in Host or Content Hosts view I guess I expected the very basic search to search for host names matching the string. It does this but I also get several other hosts that does not included the string in the host names. This makes me wonder what that search actually does. Anyone knows?

Using only a string it searches all searchable fields, better use name ~ fmproxy if you only want hosts with the string in the name field.

I seen for example that all hosts has the “Registered Through” field that contains the proxy names and I thought that must be it why it includes those hosts in my query for the fmproxy.
However not all hosts that contain this string are showing up in the search result so that is why I am a little puzzled. Is it possible to see on CLI or similar what field it finds the string in?

Perhaps with foreman-rake console, but I do not have an example for it.