Missing assortment
The customer is asking for something that is not sold. This is an assortment signal.
Advanced
Diagnosing zero-result searches before you try to get rid of them.
Not every empty search requires a synonym. First, classify the cause.
Product data
The product exists but relevant words or characteristics are missing from the indexable data.
Spelling
Typo tolerance or corrections do not sufficiently recognize the input.
Customer language
The catalogue uses a different term than visitors.
Filters
A combination of facets can reduce a valid search query to zero-result searches.
Index
New or modified products may be missing due to synchronization or index problems.