Using Adobe Search and Promote we can able to hide specific facet items. For example, you have a product type as "Lorem Ipsum" and you want to hide this facet item under "Product Type" facet, you can achieve this by adding a business rule. After adding this rule, "Lorem Ipsum" facet item is not displayed.
Rules -> Business Rule
Rules -> Business Rule
After adding this rule test it in simular or in author AEM instance.
Click here to see how to integrate AEM and SnP.