Conditional Formatting: Don't format blank cells

I used the below formula for conditional formatting when 3 conditions are met cell should be highlighted with red.

=IF(AND($L1>=8,$H1="CAR",$M1="Open"),TRUE,FALSE)

I have used 4 rules based on different categories but here i am facing a problem when any cell is blank it still shows highlighted. My requirement is if any cell is blank how to handle that condition without getting highlighted.

If all categories Column (H) can fit into one formula it is also fine.

I have attached the sample file for further explanation.

Sample File.xlsm

Thanks.