Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
nhung cong » dung cong, thong cong, hang cong
hoc thien » hoc hien, hoc thieu, hoc thiet
trung cua » truong cua, trung tuan, dung cua
trung cap » truong cao, trung tam
cong tang » cong thang, cong tan, cong lang
tang van » dang van, hoang van, trong van

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 ((trung cua) or (trung cap)) nhung cong tang van ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh ((trung cua) OR (trung cap)) nhung cong tang van ban.
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh ((trung cua) or (trung cap)) nhung cong tang van ban*.