I think you are talking about Dynamic Filters? (The Element on the left sidebar of a report that allows you to filter data on the fly) There is a section in the report builder called "Filters", and a subsection in there called "Dynamic". Switch the radio button to "Custom" and you can select all of your own Dynamic Filters. Some fields cannot be used as a dynamic filter. There is a chart at the bottom of this page that shows you what kind of fields can be used as a dynamic filter:
https://help.quickbase.com/user-assistance/dynamic_filters.html
