It's hard to say without knowing what the smell is exactly. It sounds like you cleaned carpets.

As soon as weather permits in your area, open windows for a couple of days. It's amazing how fresh air will help rid a home of odors.

Are there old curtains or blinds in the house? They might be the source of the smell if they've not been cleaned.

Is the house newly painted? If not, a base coat of Kilz and repainting might offer a solution.

Have you had the ducts cleaned? There maybe old smells in the HVAC ducts.

There are large air cleaners available at rental places. These are the kinds of things used by remediation companies after a fire to remove the smoke odors. Google removing smoke smell after a fire to see what I mean.

these are great tips. there are blinds here but it seems to be the carpet that has the smell, even though we washed them. we do plan to get our air ducts cleaned! thank you