Not a Brain here. Hair is dead. Nothing you can apply topically can help your hair grow faster or stronger. You an apply protein and help with breakage issues. That can make it seem that the product is making your hair grow faster due to stopping breakage.
You can take a biotin supplement that helps the hair grow better IF you have a biotin deficiency. Biotin causes nails to grow measurably thicker. It takes about 5-6 months to see the difference.