Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
thong cong » trong cong, tong cong, thong thong
phong tac » phong tuc, phong cac, phong tai
tac thong » tac thuong, tac trong, tac chong
cong tac » cong ty
van chat » cao chat
tac van » tac vang, cac van, tac va

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) or (dieu hanh)) - khanh phong tac thong cong tac van chat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thien hach) OR (dieu hanh)) - khanh phong tac thong cong tac van chat.
• Adding a wildcard symbol may retrieve word variants: hoc ((thien hach) or (dieu hanh)) - khanh phong tac thong cong tac van chat*.