How to speed up the loki query? Thanks very much

I have set up the loki write/querier/frontend in the K8S as dockers.
And there are one loki write 50 loki querier and 2 query-frontend.
The cache is redis . Finally the chunk and index data is stored in object storage.
However, I find that the speed of loki query is very slow.
And with the help of tempo, I capture the whole webpage as follows.