Then from 1 and 3, you get the main attributes that your candidate key should have. You try it out (trilKey+) and if it works, that is your only candidate key. If it fails you try add to it the attributes in step 4 one by one and group by group and also removing the attributes in step 2.
So it your main key derived from 1 and 3 is let’s say AB. And in step 2 you have C and in step 4 you have DE.
Then the next tries for your candidate keys would be:
ABC, ABE, ABDE. You do not include C.
Anyways, been working on a small application that should work on this algorithm. Make it easier for others.