Some problem with HTTP POST

Hi everyone, when I use elasticsearch 5.6.5 version and query REST API through HTPP POST tool all work fine.
But when I use elasticsearch 6.x.x up version, and it shows me the incorrect format error.
I know the REST has been changed after the 6.x.x elasticsearch, but I don't know how to modified the query REST API.


this query can work on elasticsearch 5.x.x, but can't run on 6.x.x up.

thank you in advance!

I wonder if this may be related to the strict content type checking that was introduced in Elasticsearch 6.0.