The National Business Registration Portal confirms whether a distributor is an active, registered entity with business lines that match the category. That establishes company facts, but registration does not prove category sales, inventory levels or service quality, so it is one input among several rather than evidence of performance.
For import-heavy categories, Vietnam customs trade data can be used to sanity-check the volumes a partner reports. Direct store checks and marketplace checks on Shopee, TikTok Shop and Lazada show whether products are actually on shelf and listed, and at what price. Together these give a view of performance that does not rely only on what the partner reports back, which matters most as a contract renewal approaches.
Coverage in Vietnam is usually agreed by province, and traditional trade, meaning independent retailers and wholesale markets, is under-represented in e-commerce and modern retail checks. In categories where traditional trade is significant, online and formal retail observations alone will understate real coverage and miss real pricing behaviour, so the sample has to reflect how the category is actually sold.