Excel Multiple IF and AND

I have this excel problem...

 if 0-20 and <= .15 DISCARD
 if 0-20 and > 15   REVISE
 if 21-80 and <= .15 DISCARD
 if 21-80 and > .15 RETAIN
 if 81-100 and <=.15 DISCARD
 if 81-100 and >15



       =IF(AND(C34<=20,C36>=0.15),DISCARD),IF(AND(C34<=20,C36>=0.16),REVISED),IF(AND(C34<=80,C36>=0.15),REVISE),IF(AND(C34<=80,C36>0.16),RETAIN),IF(AND(C34<=100,C36>=0.15),DISCARD),IF(AND(C34<=100,C36>0.16),REVISED) but yielded a "NO VALUE RESULT"

Please help me