Duong was found still alive inside her home in the 2600 block of Ponselle Court between U.S. Highway 101 and South King Road after police received a report of a shooting at 1:30 p.m., police said.
She died at 2:30 p.m. at Regional Medical Center of San Jose, police said.
Duong was well-known in the neighborhood for selling small items such as snacks out of her home, and had many customers in the area, police said.
Family members are caring for her two children, a 12-year-old son and 8-year-old daughter, police said.
The shooting occurred minutes before a scheduled lockdown drill at O.B. Whaley Elementary School, about a block north of where the shooting happened, according to Dan Deguara, director of education services for the Evergreen School District.
The drill was set to start at 1:45 p.m., but after police notified the K-6 school of the shooting, the principal ordered a real lockdown five minutes early, Deguara said.
"The drill was planned, and it happened there was an incident in the area that happened simultaneously," Deguara said.
Police gave the school the all-clear, and the lockdown ended at 2 p.m., Deguara said.
The Police Department's homicide unit is still investigating the shooting.
Anyone with information about the case is urged to call Detective Sgt. Steve Bustillos or Detective Jaime Jimenez at (408) 277-5283, make a call anonymously to Silicon Valley Crime Stoppers at (408) 947-7867 or visit www.tipsubmit.com for a possible cash reward.