Search synonyms strategy

Problem

Users search for “hoodie” but your products are titled “sweatshirt.” Without synonym mapping, those queries return zero results even when the right inventory exists.

Approach

Maintain a lightweight synonym table keyed by canonical term. At query time, expand the user’s input with all known equivalents before hitting your search index. Keep the table bidirectional so “sweatshirt → hoodie” and “hoodie → sweatshirt” both resolve.

Steps

1. Audit zero-result queries from the last 90 days. Identify the top 50 terms that should have matched.
2. Build the synonym map as a flat JSON or KV store. Example: {“sneakers”: [“trainers”, “kicks”]).
3. Expand at query time by looking up each token in the user’s input. Append synonyms with a lower boost weight to preserve original intent ranking.
4. Validate weekly by reviewing click-through rates on synonym-expanded results. Prune mappings that generate impressions but no clicks.

Pitfalls

• Over-expansion: mapping “shirt → top” pulls in irrelevant categories.
• Stale mappings: seasonal terms like “ugly sweater” need expiration dates.
• Language drift: regional variants (“flip-flops” vs “thongs”) require locale-aware synonym sets.