How to filter through Admin Web API

There doesn’t seem to be much documentation on how to filter searches. The FilterModel in the docs is just empty: https://docs.litium.com/api-reference/api?product=Litium.AdminWebApi&version=7.4&xref=Customers.Person#Litium_Web_WebApi_AdminApi_Search_FilterModel

Are there any more in-depth documentation available?

Litium version: 7.4

There are BoolFilter and TypedFilter but somehow they are not generated in the document. I will file a bug.