No. Deep scratches cannot be filled in and in some cases cannot be removed. If you drag your fingernail over a scratch and it gets caught, or slides into the scratch, then this scratch is to deep to hide and probably too deep to completely remove.

Meguiar's believes the best way to approach surface defects like scratches is to remove them, not fill them in. In the case of deeper scratches - for example someone keys your car while it's parked in a parking lot - then sometimes you are better off improving the scratch, not attempting to completely remove the scratch.

Removing a deep scratch could mean causing more harm than good if you go through the clear and expose the base coat, or in the case of a single-stage paint, exposing the primer under the color coat, which can then only be repaired by repainting the affected area.

For scratches like these you can often use a Meguiar's paint cleaner to improve the scratch in such a way that is difficult to see unless you know exactly where to look. Often times this is more acceptable than paying to have the panel or section of your vehicle repainted.