Disabling buttons

So I'm having issues at work with the staff team not paying attention two customer orders I would like to know how to disable the new sales button as people are not paying attention to the items that are on the counter versus what is on the screen as well as the little asterisk star symbol up on the top of the bar where you scan in so it pulls up what ever item you scan however it doesn't work when you have items that have numbers in the description so any ideas of disabling that that would be amazing thank you