Perhaps you should try some spelling variations:
hoc thiet » hoc thuyet, hoc hien, toc thieu
hoc thieu » toc thieu, hoc hien
trang van » trang va, trong van, tang van
dung cong » dung trong
ban thanh » ban hanh, ban hang
thanh cau » thanh chau, thanh mau, nhanh cau
tran van » luan van
cong ban » cong bang, cong san, cong tan

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: ((hoc thiet) OR (hoc thieu)) tach - hanh ((tran van) OR (trang van)) dung cong ban thanh cau~.
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (hoc thieu)) tach - hanh ((tran van) or (trang van)) dung cong ban thanh cau*.