Perhaps you should try some spelling variations:
trinh dang » trinh dung, trinh dan, trinh bang
hieu soat » hieu suat, hieu hoat, hieu luat
dang cong » dung cong
cong tuan » cong tan, cong luan, cong thanh
kien soat » kiem soat, bien soan, dien hoat
van hieu » cao hieu
kien hoa » dien hoa, tien hoa, kien ha
tin » tinh

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

• Performing a fuzzy search may retrieve terms with similar spellings: (( tin dung (luan OR quan) van hieu soat ) or ( trinh dang cong tuan ((kien soat) or (kien hoa)) ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tin dung (luan OR quan) van hieu soat ) OR ( trinh dang cong tuan ((kien soat) OR (kien hoa)) )).
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( tin dung (luan OR quan) van hieu soat ) or ( trinh dang cong tuan ((kien soat) or (kien hoa)) ))".
• Adding a wildcard symbol may retrieve word variants: (( tin dung (luan OR quan) van hieu soat ) or ( trinh dang cong tuan ((kien soat) or (kien hoa)) ))*.