No matter what I do, it seems like the house doesn't smell nice.

The scent of a candle only lasts for a moment when you burn it, and disappears when you put it out.

I also burned scented candles for a few hours (and because the smell was too strong when burning)

The diffuser only smells a little at first.

Later on, perhaps because my sense of smell became dulled, I couldn't smell anything at all.

Even if I flip the stick over, insert a new one, and do whatever else, there is no smell, and if I use it past about halfway, the smell disappears completely.

Things like room spray are gone in a second.

There were some friends whose rooms smelled nice, with a subtle scent...

What on earth is the secret?

I also sprayed every scent imaginable and ventilated the room.

I wash the bedding too, sigh...

Since the house itself is humid, I hope it doesn't even smell musty, let alone smell nice.