Phuong Le, 25, was last seen on April 25th at the Barnes and Nobles store in Fairfield.
Police are now focusing on her former boss, Thuc Nguyen, as a possible suspect.
Neighbors say police searched his home last Friday.
Le's brother said his sister worked at Nguyen's Suisun City Postal Express store for nearly two years and described him as a friend of the family.
