There are many reasons for the symptoms of bloating and nausea, vomiting and lack of appetite: 1. Whether the symptoms are due to improper diet or weakened gastrointestinal motility leading to indigestion. It is also possible that the symptoms are caused by acute gastroenteritis due to unhygienic diet; 2, whether the symptoms are caused by gastritis, gastric ulcer and other stomach diseases. If stomach diseases are excluded, further ultrasound examination of liver, gallbladder, spleen, pancreas and liver function tests are needed to clarify whether the symptoms are caused by cholecystitis, gallstones, liver cancer, hepatitis, etc.; 3, the symptoms of gastrointestinal tract caused by psychological factors. You can go to the gastroenterology department of the hospital for further targeted treatment according to the specific causes of the condition.