- * If this is TRUE, notmuch_query_search_messages will omit excluded
- * messages from the results. notmuch_query_search_threads will omit
- * threads that match only in excluded messages, but will include all
- * messages in threads that match in at least one non-excluded
- * message.
+ * If set to TRUE or ALL, notmuch_query_search_messages will omit excluded
+ * messages from the results, and notmuch_query_search_threads will omit
+ * threads that match only in excluded messages. If set to TRUE,
+ * notmuch_query_search_threads will include all messages in threads that
+ * match in at least one non-excluded message. Otherwise, if set to ALL,
+ * notmuch_query_search_threads will omit excluded messages from all threads.