There are ways of choosing five cards.
Now we need to find the number of ways of choosing a pair of threes, since there 4 suits and we chose 2 there are ways of choosing the suits for the threes. Now with the threes choosen there are 48 possible cards to choose from and from those another 44 cards to chose from and 40 cards for the last card so that the last three cards are not threes and are not the same with each other. There are are ways of choosing them because is the number of premutations we can form with them so we need to divide by it to remove this case.
Thus, the probability is,