Differnt shards giving different results

[DavidTurner]

This very closely-related question seems to be due to inconsistent synonyms on the nodes, or synonyms that changed over time:

Different primary and replica shard size

A good thought. Yes, inconsistent synonyms files can indeed result in inconsistent search results. Elasticsearch will use the current synonym file for searches and for indexing new documents but will not re-index any old documents, and this can leave your index in a very strange state. I think reindexing would be wise.

Does that apply in your case too?