Restriction on arrival will be applied only to the first day you want to book a room.
A throughout restriction will be applied to any day in the reservation.
If you have a Minimum stay restriction on arrival for 7 days for May 1 and 7, you will not be able to book for 5 days only if the initial booking date falls on May 1 or May 7. But you still can reserve the room from May 2 to 7 or from April 31 to May 4.
If you have a Minimum stay throughout restriction for 7 on May 1 and 7, then you will not be able to book a room for 5 days if any booking day falls on these days. You can't reserve from May 4 to 9 or from 5 to 10, but can do it from 2 to 6 only.