Dirt gets embedded between the planks of hardwood floors and dulls the shine of the wood. Flat mops can't get at the dirt wedged between the wood. Remove the dirt between the wood regularly so it doesn't get packed down and more difficult to remove. A quick change to your cleaning routine will change the whole look of your room with hardwood floors.
Sweep the floor to remove any dirt on top of the wooden planks. Choose a bloom with fine, exploded ends for best results.
Insert your dull knife between the planks. Use a small enough knife that you don't have to force it. Move it around to break up the dirt. Repeat between every plank where dirt is trapped.
Attach the bare floor attachment to your vacuum. Use a vacuum without a beater bar because it can dent your finish.
Run the vacuum over the wooden planks to suck up the loosened dirt and grit.