Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
hoc thien » hoc hien, hoc thieu, hoc thiet
trinh cua » trinh luat, trinh quan, trinh luan
trong ban » trong san, trong quan, trong cac
trong tan » trong quan, trong cac, trong ca
thanh van » thanh san, thanh toan, thanh phan
tinh cua » sinh cua, tinh chat, tranh cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien hach - hanh ((trinh cua) OR (tinh cua)) dung ((trong ban) or (trong tan)) thanh van~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh ((trinh cua) OR (tinh cua)) dung ((trong ban) OR (trong tan)) thanh van.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thien hach - hanh ((trinh cua) OR (tinh cua)) dung ((trong ban) or (trong tan)) thanh van".
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh ((trinh cua) OR (tinh cua)) dung ((trong ban) or (trong tan)) thanh van*.