The filter primarily provides you with 3 different options to filter the overall audience.
1 - Audience Size - This will enable you filter results based on the minimum and maximum size of the audience in your searched keywords results.
2 - Targeting Types - This provides a list of basic targeting provides by Facebook which includes, demographics, education, interests and more.
3 - Filtered words - This feature enables you to include or exclude certain words from the search results.
When you exclude a certain word, all results that contain that word will not be shown in your search results. When you include a certain word, only the results that contain that word will be shown in your search results. This means that all search results that don’t contain that word, will not be shown.
In case you prefer an explanation using video, we recommend watching the following video: