This how-to page is meant for developers and or sysadmins to explain in-depth how to configure the Find bar:

Find bar configuration contains:

• • suppliers --  which suppliers should be enabled*

https://git.magnolia-cms.com/projects/MODULES/repos/find-bar/browse/src/main/java/info/magnolia/findbar/FindBarConfiguration.java

Only way to configure so far is by DI. E.g. Add to your module descriptor:
<component>
<type>info.magnolia.findbar.FindBarConfigurationProvider</type>
<implementation>com.example.CustomFindBarConfigurationProvider</implementation>
</component>

Cedric says this should rather be done using YAML files. Not sure if we should document current implementation or wait until a friendlier solution is implemented.
>>>Document DI method for result suppliers