If I have sinus problem and eye itch which should I buy?

I read something about these two and they both claim to help with sinus problem.

Also come to my attention is air dehumidifier, which is the opposite of air humidifier, also claims to help with sinus problem. I saw a pamplet from hospital today claiming that dehumidifier can help starve dust mites and help with sinus problem.

So which should I buy?