I need a formula for IF a cell contains the word SYSTEM OR is empty then return yes or no

My problem is that I need to create a formula that identifies if a cell (02) is blank and has the word ‘system’ in it. It then needs to return yes or a no if there is something else other than system.

I came up with this initially:
=IF(AND(O2="SYSTEM", O2=""), "Yes","no")
Returns: no
I left O2 ="" because the value of a blank cell is 0

>Solution :

So:

=if(or(o2="system",o2=""),"Yes","No")

Logic with if() is ask the question then provide the values for true then false.