Custom fields can be displayed in search results so that your customers can easily find them.
Before you can start to setup your product filters, you need to create Custom Fields first.
Please refer to the article "Product Custom Fields" under Custom Fields section in this documentation
All you need to do to make your fields searchable is to enable the "Searchable" option from the field edition page.
Navigate to [any Joobi product / eCommerce] >> Tools >> Models & Fields or Catalog >> Fields Edit your newly created fields and enable "Searchable".
Once this option is active, your field should display in the Store Catalog Search result.