Article in English: You can use just one oil on your hair, or two to three oils. It all depends on how much money you want to spend and how intensive you want your oil treatment to be.  The two basic types of oils are carrier oils and essential oils. Carrier oils are used as a base into which the more concentrated essential oils are mixed. Many people choose to use carrier oil alone on their hair. You don’t need to use essential oil if you don’t want to. Essential oils are more highly concentrated. After diluting them with a carrier oil, you apply them to the scalp and roots only. Whether or not you decide to dilute an essential oil into a base oil, you will need a base oil. There are a wide variety of options to choose from, each offering different benefits and drawbacks.  Almond oil: Almond oil is rich in vitamin E and healthy fats that does wonders to the hair. It's particularly effective at treating dry flaky scalp and dandruff.  Argan oil: Argan oil is a Moroccan product rich in antioxidants. Although users swear it produces dramatic improvements to both hair and skin, it can be pricey. Any inexpensive Argan oil you find on the market is likely inauthentic and not worth the money. Avocado oil: Avocado hair is a favorite among African Americans who wear their hair naturally. It’s loved for its super-moisturizing power, and it’s inexpensive to boot! Castor oil: Castor oil is thought to stimulate hair growth and  decrease hair loss, treat dry scalps, prevent split ends, and increase shine. However, it’s a thick, gloopy oil that many don’t like the feeling of. If you use it, you should dilute it with a thinner oil, like grapeseed oil. Coconut oil: In addition to adding moisture to hair and scalp, coconut oil is also rich in protein. This can help heal damaged hair, which is composed largely of protein itself. One drawback is that coconut oil can turn solid in cooler temperatures. To melt it, you can warm it in your hand before use or place it in the microwave for 2-3 seconds. Extra virgin olive oil: EVOO is thought to prevent...

Summary in Vietnamese:
Quyết định nên dùng bao nhiêu loại dầu. Chọn dầu dẫn/dầu nền. Chọn tinh dầu.