Minor Scratches
For minor scratches in your laminate floor there are special, color-coordinating pencils that may be used to fill the scratches.
Seam Gaps
For gaps between plank seams the manufacturers recommend colored filler touch up products. Follow the manufacturer's instructions for these products.
Chips
For chips, deep scratches and gouges there are colored burn-in sticks available which are used with special electric knives to repair these areas.
If the damage to the plank is too severe you can have the damaged plank replaced without destroying the rest of the floor. For plank replacements there are special tools, router bits, and wood splines to make the chore easier. Unless you are real handy I would leave the plank replacement to a professional installer.