See the review tab at the top of the page. Click on it, then go to "search reviews" then look for the drop down "city" , highlight Orange County. Then scroll down further and look for the drop down "ethnicity"
find Asian.  There are obviously tons of other parameters you can fill out. Then hit "search" and let the TER search engine do it's thing. You should see names like Michikoo, Yumi, Dee, Thai Dara etc.
Also if you want to go the agency route try IslandGirlsToday.  Of course, you'll need to be VIP to get the full benefit of the TER reviews. And have your screening info/references ready to go, you will be screening.