There's 5 mushrooms each day (sometimes 6, if you have tree stumps). 4 of those will be regular mushrooms, 1 should be mush furniture. Maybe you're not finding all of the mushrooms?
A suggestion is to clear flowers away from your trees to make sure they have a place to spawn too. They can also spawn on ANY side of the tree. Front, left, right, or even behind it.
I guess because I didn't not remove the regular mushroom from yesterday and the day before =(
I'm now trying to clear flowers away from trees, hope it will work =)
@PinkWater: are you sure!? I'll pay you with bells or hybrids!