In e-commerce product search, semantic retrieval starts with a constraint: a result is only as trustworthy as the catalog revision, tenant boundary, and source identifier that travel with it. An unbounded nearest-neighbor call can return plausible product text, but it can't explain why an unavailable SKU appeared twice. Short answer: use a staged retrieval design with explicit collections, bounded queries, and source context that can be traced back to the exact e-commerce document. That ch...