Hello,
Unfortunately, there is no possibility to select multiple OUs/containers or use an LDAP filter in a similar way. The thing is that wildcards are not allowed for DN syntax properties (e.g. distinguished name) in LDAP filters. The restriction comes from Active Directory itself, not Adaxes. If the objects that you need to be available for selection have specific property values, then using an LDAP filter will work just fine. For example, in case of the Modify User action, the following LDAP filter can be used to allow selecting only users whose department is Sales or IT Staff:
(&(sAMAccountType=805306368)(|(department=Sales)(department=IT Staff)))