There are several ways to deal with a scratch in your wooden furniture.
1. A surface scratch can be camouflaged with a marker in a color that closely matches the color of your wood. Such special markers can be found in a hardware store, or in the hardware section of variety stores like Wal-Mart.
2. A scratch that is a little deeper than a surface scratch can likely be repaired with paste wax or even melting colored wax that matches the color of the furniture.