Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
trung tuan » trung thanh, tran tuan, truong thanh
phung cong » nhung cong, phong cong, nhung chong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
cong tan » cong tac, cong san, cong thanh
tran tan » tran tuan, tran van, tran thanh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet tach - thanh ((trung tuan) or (trung tam)) phung cong tan tran tan~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - thanh ((trung tuan) OR (trung tam)) phung cong tan tran tan.
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - thanh ((trung tuan) or (trung tam)) phung cong tan tran tan*.