I looked into this and to get the results to return as expected a 'Query Cleaning Rule' should be created.A basic version for this is:Condition(s):Every QueryPerform the following action(s):Perform regex on backend parameter sp_q pattern ^(.*)$ substitution $1*

Additional features that are available:·         File crawler·         Multi Value ,Range and single value filters·         Records Search and dimension/Facet search (not sure exactly what you mean here)·         Thesaurus, phrases·         Datasources support (not sure exactly what you mean here)· ...

This can be done via Attribute loader:https://docs.adobe.com/content/help/en/search-promote/using/settings/c-about-metadata-menu.htmlTo be able to utilize Attribute loader, Support will need to first enable this option/feature.