I also have some strange issues with search in Outlook (2010, 2016, 2019) and Grommunio-Web too.
And yes... on Android (ActiveSync)...
I already mentioned that in my post
In Outlook the search gives results in "bad order" (random) instead of newer-to-older
The same is in the web-ui... where the only (time) filter that works is "two wees"
On ActiveSync I newer get ANY results (timeouts?)
The actual mailbox I'm using/testing on has approx 50GB and 250K items of those approx 150K in the "inbox" alone (I know, I know... but it is what it is)
Tried the re-index a few times with no changes
And yes... I see errors like grommunio-index-run.sh[88895]: [ERROR] Failed to insert message 13/4087785: exmdb call failed: Dispatch error
hints?