Perhaps you should try some spelling variations:
knowing about » known about, know about, knowing your
lang oanh » lang lang
oanh tran » anh tran, anh tuan, binh tran
tran duc » tran dat, tran dai
duc oven » duc vien
kong siu » kong eiu, wong siu, dong sin
von sam » von sa, von sap, von scham
king » wing, kind, ping

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: lang oanh tran duc oven king john ((von sam) OR (((kong siu) OR (knowing about)))) ;~.
• Adding a wildcard symbol may retrieve word variants: lang oanh tran duc oven king john ((von sam) or (((kong siu) or (knowing about)))) ;*.