There's another way? Because you still can't choose what effect to get if the ingredients have more than one in common, right?
I do have that perk, but no matter the knowledge, the game is still the obstacle

I think you need to take a closer look at the effects of the ingredients you're using, and
all of the effects of the potion you're brewing. If both ingredients have restore health and restore magicka, it may be called a "Potion of Restore Magicka," but it will restore
both health and Magicka. This will be reflected in the potion's description. The name thing is annoying, but it will still work.
The Purity perk for Alchemy will make it so that your potions don't have negative effects on them, and your poisons don't have positive effects on them--that way, you don't have to worry about having a restore health potion that also paralyzes you or something like that. However, in this case, you're just going to have to put up with a potion that restores your health and your Magicka.