Perhaps you should try some spelling variations:
trinh nang » tinh nang, trinh bang, trinh mang
hieu soat » hieu suat, hieu hoat, hieu luat
kien soat » kiem soat, bien soan, kien hoa
suat van » suat va, sat van, suat nang
van hieu » cao hieu
uan luan » quan luan, dan luan, han luan
san luan » dan luan, tang luan, hang luan

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( trinh nang suat van hieu soat ) or ( tinh quang ((uan luan) or (san luan)) kien soat ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( trinh nang suat van hieu soat ) OR ( tinh quang ((uan luan) OR (san luan)) kien soat )).
• Adding a wildcard symbol may retrieve word variants: (( trinh nang suat van hieu soat ) or ( tinh quang ((uan luan) or (san luan)) kien soat ))*.