Fenugreek Seeds:
Fenugreek seeds can also help grow thick eyebrows. They are rich in protein as well as nicotinic acid and lecithin that promote hair growth. The seeds also help in rebuilding hair follicles.
What you have to do is Soak 1 teaspoon of fenugreek seeds in water for at least 5 hours. Grind the soaked seeds into a thick paste, then add a little coconut oil or almond oil. Apply the paste on the brows just before going to bed and leave it overnight. Wash it off in the morning with warm water. Follow this remedy 2 or 3 times a week for 2 months.