I need help.

I have conditional formatting setup to highlight the lowest 4 numbers in a row. The problem I am having, is some of the numbers may be duplicates. I don't care about duplicates; in this case, each number should be considered as separate numbers.

Here is an example:

36 26 18 21 37 22 0 0 36 27 28 28 30 24 28 26 <----This one comes out OK. 18, 21, 0, 0 are the lowest four.
0 34 33 46 26 46 46 0 43 0 0 0 41 0 0 0 <----This one is not ok. There are more than 4 zeroes and it counts all of them as one number. I need to only count 4 cells.
31 24 34 27 34 37 37 0 28 36 40 32 28 37 33 28 <----This one has problem as well. It highlights 24, 27, 0, 28, 28, 28. It is counting each 28 instead of just the first four cells.

I hope this makes sense.