Regarding the Vietnam War, history textbooks in different countries and political backgrounds may present the facts in different ways. Some textbooks may indeed ignore or downplay certain events or viewpoints. This phenomenon may occur in any country's education system, because history is usually written by the victors or dominant powers. The following are some aspects that may be ignored or covered to varying degrees in some versions of textbooks: 1. **Causes and background of the war**: Some textbooks may not fully describe the complex causes of the Vietnam War, including colonial history, the Cold War background, and the political and ideological conflicts between North and South Vietnam. 2. **Civilian and soldier experience**: The impact of the war on the lives of the Vietnamese people and the soldiers who participated in the war, as well as the trauma and humanitarian disasters caused by the war, may not be fully described in some textbooks. 3. **The use of chemical weapons**: The use of chemicals such as "Agent Orange" and its long-term effects on the environment and health may not be emphasized enough in some versions. 4. **Peace movement and anti-war sentiment**: In the United States and other countries, the peace movement and public protests against the Vietnam War may be simplified or ignored in some textbooks. 5. **The outcome and consequences of the war**: The political, economic, and social consequences of the war, as well as the post-war development path of Vietnam, may not be fully described in some editions. Each country or region may be influenced by its own political tendencies or social values when writing textbooks. Therefore, understanding the full history of a complex event such as the Vietnam War may require reference to multiple sources and viewpoints.