The user wants to know who created some records. But when setting up a saved search for these records, the field Created By field is not in the list of available Fields/Filters.
Some types of entity records (e.g. Employee and Relationships) do not benefit of this Field or Filter in Searches.
The user can however determine the record's creator by:
2. Set its Summary Type=Min
The Search's Results page now displays a column with the earliest value of the Set by fields – in other words, the record creator's name.