I'm assuming you're looking for a quicker but still manual way:
Enter Find mode
type "g" into Key 3
choose "New Record/Request
type "s" into Key 1
hit enter result = most of the records you Dont want
Choose "Show omitted only" result = records you might want
Enter find mode
type "a" into key 2
choose "Constrain found set"
hit enter result = only the records you want :)
If this is something you do often, you might want to write a script for it. Scripting has "Omit Records" as an option to omit multiple records based on a criteria.
Thanks for your reply, it worked - I got what I wanted.