There may be a search result that does not display the facets on left navigation.

Example

Explanation

The reason for this being that there are no further options. Many sites have logic in place that will automatically redirect a customer to the product detail page when there is only one result matching the search criteria. There is a way to customize this setting using the workbench.

Customizing This Setting

Navigate to the Workbench > Data Configuration > Facets.
Select the facet you wish to modify and click on the green pencil icon to the left of the name.
Scroll down to the "Checkbox & Link List" section.
In the image above the Max Number of Filters is set to 1. This means that when there is a minimum of one result, the facets will not display. If you wanted the facets to display regardless, you could set the minimum to zero.

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