Search across many types became to work incorrectly

I have some elasticsearch index with 6 types in it.
Recently I've found an issue. When I performing 1 query across many types,
it didn't return results of some types, even if query matches them.
Here is the simple example.

If I performing query like these:
curl -XGET "http://127.0.0.1:9200/fts/comment/_search" -d "{my_query}"
curl -XGET "http://127.0.0.1:9200/fts/category,comment/_search" -d
"{my_query}"
I get some results, because my_query matches some documents that have type
comment.

But if I do one of the following:
curl -XGET "http://127.0.0.1:9200/fts/category,product,comment/_search" -d
"{my_query}"
curl -XGET "http://127.0.0.1:9200/fts/_all/_search" -d "{my_query}"
curl -XGET "http://127.0.0.1:9200/fts/_search" -d "{my_query}"

I get no any results, although my_query is the same and it should match
some comments.

About 2 months ago everything was working ok, but recently I've noticed
such problem. There was no any changes during this period, except everyday
adding of new documents and adding of a new slave non-data cluster node on
other physical server.
Is it a bug or what? Is there any workarounds?
Any help would be appreciated!

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