The search team began work Thursday, looking in the waters of the Wilmington and Cabrillo Marinas using sonar.
The company was hired to look for Laci Peterson after she disappeared in 2002 and for the wreckage of Space Shuttle Columbia after it broke apart in 2003.
John Steven Burgess is now in prison after pleading guilty to involuntary manslaughter.
Burgess says he met then 19-year-old Jou on Craigslist in 2007.
He claims to have dumped Jou's body into the Pacific Ocean after she overdosed on drugs she took at a party at his house.
Experts say given the time that Jou has been missing and the likelihood of decomposition, she may not be found. But they emphasize the effort is worth it to give the parents some possible closure.