Edit keywords in Atos Professional 2020

[[Ra...]]

HI,
I work in Professional 2020. I have a few questions.
- in the project keywords I have several values saved, e.g. date, operator, part number, KW status, derivat, machine, etc.
 In the key "operator" after expanding the list I have several entries (names) I would like to remove 4 names. 
I don't want to do this with "delete history" because that way I'll delete the rest of the records I'm using.
How do I delete selected entries?