[Users] Problem searching cm 4.3.0

[claws at sritch.com]

CM 4.3.0 on Opensuse Leap 15.6 current.

I'm having problems with the search. Something's not right.

1. Start CM, start at Mailbox (MH) top level
2. Quick search: from/to/cc/subject/tag: type in part of the email
address I'm looking for.

Most often (not always), CM will find the emails. The folders with the
emails will have the magnifying glass on the left of the folder.

If I retry the same search. It will not find them. Even if I switch
to the extended search > edit > header > from > check mark on for
case sensitive

- Do I have some wrong setting? 
- I'm doing something wrong? 

I had no problem searching when I was using CM3.x

What should I look for?

Thanks