It's all there. What Dorax suggested is sound advice. You may also use the special power on your house key while inside the house to repopulate the furniture after a reset.
It does not automatically populate after a reset, so if you log into the interior of a house after a reset, it will be empty until you do one of those two things.
Note that if for some reason the furniture items were broken/destroyed through some form of damage (i.e. not removed using a furniture tool), neither of these techniques will work and you'll have to wait until the next server reset before the furniture will repopulate.
