You mention it returns all manufacturers? Even after you apply filters (don’t see filter in your example)? You can control how many facets are returned with facet.limit and you can use face.pivot.mincount to determine how many facets are returned. If you calculate sum on all manufacturers, it can last.
Maybe you can try json faceting. Something like (url style):
Monitoring - Log Management - Alerting - Anomaly Detection
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