This is how you use data, not emotion!
If you go into cash register reports
Select Top N Stock sales for a given period
Now select initially a short period say the last few days and ask for a report by profit.
This gives you a list of your most profitable items.
Now look through the list to make sure that you have sufficient stock on hand (SOH). A good seller today is most likely to be a good seller tomorrow.
Check to see what opportunities you have to improve your profit, as these are the items that are working for you.
Are they in the best position? Are they being properly displayed? Maybe they should be in more than one position. Perhaps if you make them a bit more noticeable to your shoppers by locating them at the entrance or the checkout counter, where they can produce more.
Is there any wiggle margin perhaps you can try increasing your prices slightly on these items since they are popular.
Are your employees focusing on them enough?
Dramatic improvements can be made by examining your performance constantly.