The items that you select before hitting ‘queue’ should be the ones that appear in your lesson quiz.
Do you mean words that you literally just did the quiz on, or words that you’ve previously learned and have been in the spaced repetition system for some time?
If it’s the former: you have to get an item correct (without first getting it incorrect) in the lesson quiz in order for it to join the SRS queue. The lesson quiz has unlimited overrides by default if you don’t want this behaviour however, so you can just override incorrect answers until you get it correct.
If it’s the latter: if you get an item wrong eight (I think) times, it will be bumped back to your lesson queue, as it has been deemed a leech. This lets you ignore the item until you want to add it back so that it’s not wasting your time in the meanwhile (or just decide to trash it forever if it’s not worth the effort) and gives you an opportunity to look back over it properly before doing so.