Hello fellow achievement hunters,
To get both bonuses in one classic game, you will have to score 63 points or more in the upper section and you have to throw 2 yathzees to get the bonus in the bottom section.
The 63 points are really not hard to achieve, try to get each number 3 times and you should get it
3x1=3, 3x2=6, 3x3=9, 3x4=12, 3x5=15 and 3x6=18
3+6+9+12+15+18 nets you 63 points. If you somehow only threw two 5's, try to get one extra 2 and 3 to get it even again.
For the bottom bonus, I can't give much tips since this will require luck. When you throw 3 of the same kind at the first turn, keep them and try to get those other two numbers with the same value of the ones you've kept. For those who don't know, a yahtzee is rewarded after throwing 5 dices of the same value (example: five times 3).
Additional notes: When you scored your second yahtzee with a value you have already filled in on the top, you can pick any bottom category for full points. Example: you scored a second yathzee with all 5's but the only field left is Full House, you will get your 25 points anyway.
Good luck!

- MCoreBE