put https://prod.cg.optimizely.com/resources/synonyms
When you write a query, you can use synonyms to expand the keywords to get results that users otherwise may not have found.
This reduces the problem of getting too few or no results, leading to fewer chances of conversions or even search abandonment.
For example, if you search for "H2O", you mat want to find results that contain "water".
This happens when you store synonyms in Optimizely Graph and enable them per field in your query. Otherwise, many relevant results may not be retrieved.