CHINAFIFA, I will try to translate. Mumble, bumble, mumble, bumble, .....Staples Policy is as follows:
<< If you find a lower price, anywhere else, on a new identical item, just show us the lower price when you buy the item at Staples or within 14 days after your Staples purchase - and we'll give you 110% of the difference >>
American Express Blue Policy is is they do not price match stores that price match themselves. If you wait 14 days to submit your price match to American Express -- Staples time will have expired, they will not price match because it is too late, so AmEx should do it without any issues.
Did that help