Combining FTS and Key-Value indexes in one N1QL

I have query that looks something like:

SELECT r.*
FROM B234 r
WHERE r.docType=‘UmBus’
AND SEARCH(r, {“must”: {“conjuncts”:[
{“field”:“adP1DNa”, “match”: “NY”},
{“field”:“adP2DNa”, “match”: “New York”},
{“field”:“bpyCoNa”,“Fuzziness”:1, “match”: “Alex”}]}},
{“index”:“FTSIDX”})

Where FTSIDX is Full text index, it covers all the fields give in the query. I also have another, Key-Value index KVAdr that covers only adP1DNa and adP2DNa. I’m trying to utilize KVAdr for exact matches and speed, because Key-Value will be faster than FTS. Is it possible to utilize KVAdr and FTSIDX in a single query ?
Thank you !

Assume KVAdr is GSI. If you want use GSI Index give AND predicate that uses GSI.
If query is not covered If both indexes qualify it does IntersectScan. Which may perform poorly.

You have the following options.

FTS queries can cover very narrow cases. https://blog.couchbase.com/introducing-fts-with-n1ql/
i.e. FTS index has all the entries and no false positives are possible, Predicate has single SEARCH(), no other predicates, Projection has only document key, SEARCH_SCORE(), SEARCH_META().

Options 1: Assume following query is covered get the document keys and use SDK fetch full documents

SELECT RAW META(r).id
FROM B234 r
WHERE r.docType="UmBus"
AND SEARCH(r, {"must": {"conjuncts":[ {"field":"adP1DNa", "match": "NY"}, {"field":"adP2DNa", "match": "New York"}, {"field":"bpyCoNa","Fuzziness":1, "match": "Alex"}]}}, {"index":"FTSIDX"});

Option 2: Assume your query covered by projecting document key only (ie. subquery) use parent query get documents.

SELECT r1.* 
FROM B234 AS r1 USE KEYS (SELECT RAW META(r).id
                          FROM B234 r
                          WHERE r.docType="UmBus"
                          AND SEARCH(r, {"must": {"conjuncts":[ {"field":"adP1DNa", "match": "NY"}, {"field":"adP2DNa", "match": "New York"}, {"field":"bpyCoNa","Fuzziness":1, "match": "Alex"}]}}, {"index":"FTSIDX"});
);