First, read the English article below.

With every day that passes between the last time you used drugs and the date of the test, your chances of passing go up. If you have any time at all to prepare, use it wisely and stop using drugs until you're well in the clear. No matter what type of drug you've been using, you're better off stopping well in advance of the test rather than relying mostly-ineffective methods for faking the test.  If the drug test is to be administered by your employer, in most cases you should get fair warning in advance of the test. You might not know the exact day it'll be administered, but you might know what week to expect the test. Pay attention to your company's policies so you can prepare for the test instead of getting caught off-guard. If you're being tested because you're on probation, your tests are likely to be on a set schedule. Don't let the test date sneak up on you; get your body ready in advance. Of course, it's not always possible to prepare for a test. If you get pulled over and the police officers suspect drug intoxication, you might have to take a test on the spot. While a test with no notice is tough to pass, there are still things you can do to give yourself a better chance. There are four types of drug tests: urine tests, blood tests, saliva tests and hair tests. The standard 5-panel test tests for amphetamines (speed, meth, crank, ecstasy), cannabinoids (marijuana, hash), cocaine (coke, crack), opiates (heroin, morphine, opium, codeine), and phencyclidine (PCP). Advancements in testing technology have made it difficult to fake tests, but knowing the differences between the tests can be helpful when it comes to your specific situation. Here's the breakdown:   Urine tests are the most common type of tests administered by employers. They're the easiest tests to tamper with, since you have a small window of privacy during which you're supposed to provide a urine sample (provided you aren't being watched).  Blood tests might be administered if you get pulled over and drug intoxication is suspected. This... 

Now, please write a short abstract for it in Vietnamese. Abstract:
Dành ra khoảng thời gian càng dài càng tốt. Tìm hiểu xem bạn sẽ bị kiểm tra theo phương pháp nào. Thử xác định xem lượng chất ma túy trong cơ thể bạn là bao nhiêu. Biết nên chọn loại xét nghiệm nào.