Client::search() wont give the same answers as the dev tools in Kibana

[benlabbe]

I'm facing a problem of coherence in the answers of elasticlient::Client::search() versus thoses displayed by Kibana . Same problem when I use elasticlient::Client::Scroll
On my personal debug config (docker.elastic.co/elasticsearch/elasticsearch-oss:6.2.2 and docker.elastic.co/kibana/kibana-oss:6.2.2) , I observed that the number of total _shards strongly differs in the results of elasticlient::Client::search() and Kibana : 5 _shards with search(), vs 21 in Kibana.