You can wrap your formula with the IFNA command with the modifier set to nothing. So for example something like CONCATENATE(B3,D3) would then become IFNA(CONCATENATE(B3,D3),""). That tells the formula to take anything that would result in NA and just leave it blank. IFNA is for NA and the last part with the 2 double quotes is what should be displayed. Leave it empty and it'll be blank.
You can also then go under Options > Advanced > scroll down to Display Options For This Worksheet and find the box for 'Show a zero in cells that have zero value' and make sure that's unchecked.
With both of those together any cell that should be NA or 0 will just be blank.