Kim Tran, who has run a food truck outside different Washington tourist attractions for around 20 years, said business is slow because the Smithsonian museums are closed, even for the winter months when vendors usually see less customers. Cheyenne Haslett/ABC NewsKim Tran, who has run a food truck outside different Washington tourist attractions for around 20 years, said business is slow because the Smithsonian museums are closed, even for the winter months when vendors usually see less customers. Cheyenne Haslett/ABC News