Additional help on a formula change:

This formula works IF(ISERROR('Piazzo Ware'! C30),"", 'Piazzo
Ware'!C30) however I have an additional question;
how do I make this look in C74 and if there isn't a value there go to
C63, no value, go to C52, no valur look into C41, agin if there isn't
a value then go to C30?

Thanks