Having trouble with function.
 

I am trying to keep track of the aerial photographs we have on file and also
to easily determine if the Site we have is within an aerial photograph we
have on file. The function is below. (I can't seem to find how to attach the
file...) It sometimes gives me the right answer and sometimes doesn't.

Thank you for your help!

=IF((AND((D4-11.5*B4)<$H$4<(D4+11.5*B4),(E4-11.5*B4)<$I$4<(E4+11.5*B4))),A4,"Do Not Have")