It does not cover all possibilities and in case of problems you certainly still should visit a qualified medical doctor. This is especially true for vaccinations. Depending on the country you are travelling, medical facilities may not be widely available. This is true especially for Cambodia, Laos and Myanmar. China and Vietnam does have a wide variety of medicines, but you may not be familiar with them.
Chinese people are very aware of health problems.
However, Western medicine is not very widely available. Doctors and hospitals normally expect immediate cash payment. If you regularly need some medicine, bring enough of it with you since chances are that you will not get the same or a replacement for it. It is also recommended to bring one or two clean needles in case of an emergency. Be carful not to drink water directly from the tap.