You don’t want the stain remover to ruin your upholstery, so be sure to test any stain remover first on an inconspicuous spot before using it. For stubborn stains on leather upholstery, pretreat the leather with a leather conditioner. Then apply a leather stain remover on the stain and rub it in. Allow it to sit for about 30 seconds and wipe off the stain remover. For ink stains, use hairspray or rubbing alcohol mixed with water. Spray the hairspray on the stain and blot carefully with a damp, clean cloth to avoid spreading the ink or letting it run on the upholstery. For greasy or oily stains, such as lipstick or food grease, use a watered-down paint thinner formula and a cotton cloth. Put a little bit of paint thinner in a cup and add an equal amount of water. Dip a cotton cloth in the cup and rub it into the stain. Sprinkle the stain with salt or cornmeal and let it sit overnight. Vacuum this section of the upholstery. Be sure to test the paint thinner on your upholstery to make sure it will not stain or ruin the material. If you happen to spill coffee, dilute the coffee with cold water and blot with a paper towel. Apply some glass cleaner and let it sit for 5 minutes. Blot again with a paper towel to lift up more of the stain.  Always blot stains. Never scrub them, so that they are not rubbed further in to your vehicle's upholstery. If the coffee is still visible, scrub the upholstery with dishwashing liquid and rinse with warm water. Blot the area again with paper towels. Dry the area with a hair dryer. Hold the hair dryer at least several inches away from the spot so that you don’t scorch the upholstery. If someone gets carsick in your vehicle and vomits on the seat or the floor, clean it up as soon as possible to prevent it from setting into the upholstery. Wipe up excess vomit and dilute the stain with cold water. Wash the area with mild soap and warm water. Then neutralize the stain by pouring a small amount of club soda on a cloth and blotting it on the stain. Alternately, you can use a mixture...

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Write a summary of the previous text in Vietnamese:
Thử sản phẩm tẩy rửa trước khi sử dụng. Xử lý trước những vết bẩn cứng đầu trên chất liệu da. Tẩy vết mực. Loại bỏ vết dầu mỡ. Tẩy vết cà phê. Làm sạch chỗ nôn ói. Tẩy vết máu.