If your nose is stuffed up but not dripping, or mucus isn't coming out easily when you blow your nose, don't force it. Your impulse may be to blow your nose until you expel some mucus, but it's best if you leave the tissues alone. Only blow your nose when it is running. Drinking lots of fluids when you’re sick can help clear up a stuffy nose. Stick with plain water, herbal tea, or broth and keep a water bottle or mug on hand at all times to encourage hydration.  Comfortably hot beverages are especially helpful for thinning out mucus. Avoid sugary beverages like juice and soda since they don't contain any helpful nutrients or electrolytes your body needs. Sugar may also prevent your immune system from functioning properly. Stay away from caffeine, such as in coffee, as it can be dehydrating. Lying flat on your back can cause mucus to build up while you rest or sleep. Elevate your head with a few pillows or snooze in a recliner when you have a stuffy nose. If you typically sleep on your stomach or side, try sleeping on your back and elevating your head while you're sick. Irritants like cigarette smoke can make a stuffy nose worse. Avoid smoking or being around others who smoke when you’re congested. If your stuffy nose is due to allergies, do your best to avoid common allergens, like dust and pet dander. If you need help to quit smoking, speak to your doctor or contact the Quitline at 1-800-QUIT-NOW.

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Write a summary of the previous text in Vietnamese:
Xì mũi nhẹ nhàng. Uống nhiều nước để làm loãng dịch nhầy. Gối cao đầu khi nằm. Tránh xa các yếu tố gây kích ứng.