EXCEL 2003

TAB "SHIPPED"
Column "A" is a list of serial numbers.
Column "B" shows the ship date of the product.
Column "C" is called "RETURN DATE".

TAB "RETURNS"
Columns "A" & "B" show s/n and return date of the products that shipped in
"A" & "B" of the "SHIPPED" tab.

I want to lookup the return dates of the serial numbers in tab "RETURNS" and
find the s/n with the return date than "B" in "SHIPPED". There may be
mulitple returns for the same s/n. Some may be < the ship date and some
the ship date.

I tried VLOOKUP but it only returns the first match. I need to know if the
shipped product ever came back as defective. (I.E. Return Date Ship Date
for a given s/n)