On Kibana 5.5.0 there is a link for lucene query page documentation [0].
It now returns a 404.
I believe the page has been renamed [1] and if you look closely you will see that the url change a bit (5.x vs 5.5).
This page is really good and that will great if the 404 can be fixed.
Thanks in advance.
[0] https://www.elastic.co/guide/en/elasticsearch/reference/5.x/query-dsl-query-string-query.html#query-string-syntax
[1] https://www.elastic.co/guide/en/elasticsearch/reference/5.5/query-dsl-query-string-query.html#query-string-syntax