> one last question: AND operator is implicit (by default) ? Any other > accepted ?
Boolean search prefixes (the tag:, severity:, is: prefixes, etc.) work with an implicit AND. Free text search terms work with an implicit OR. Also, when the same boolean prefix occurs twice (for example, tag: in "tag:unanswered tag:team-python"), there is an implicit OR between them. There are several other operators as well. See https://getting-started-with-xapian.readthedocs.io/en/latest/concepts/search/queryparser.html for a more detailed description. All search results are sorted first by relevance score, and then in the order of recent activity. Always happy to answer more questions! And, please feel free to ping me to improve documentation, help messages, etc.
