Please check your configuration. You had some custom field values set to sample values: https://i.imgur.com/UoUXQgH.png
So the search probably tries to match these sample values, but they don’t exist.
Also check the documentation first on this, it’s explained there with details: http://wp-dreams.com/demo/wp-ajax-search-pro3/docs/#frontend_search_settings_creating_custom_selectors_from_custom_fieldsBest,
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