How many decks are we playing with?
There are 4 8s in the game and in Hold’em all players may use the 5 community cards and their 2 hand cards, best hand of 5 cards is made out these 7 cards.
With 3 8s on table and 1 8 in your hand you have four of kind 8s, with 3 8s on table and a pair of 4s, you have full house, 8s over 4s.
With 2 8s on table and 2 8s in your hand, you have 4 of a kind 8s. With 2 8s on table, 2 4s on table and 1 4 in your hand, you have full house, 4s over 8s.