The examples use codes such as 1_4_7 which means article with id=1 combined with article with id-4 combined with the one with id=7.  That's great, but where do you find these ids to use them when setting preferences?

The easiest way is to follow a TERMS link while logged in.   Instead of just a number list of links, each link will show its code. Also, at the end will be a link to a table of article numbers, useful for use in spreadsheets.