Perhaps you should try some spelling variations:
thien hach » thien thanh, hien hanh
cong thanh » dong thanh, cong trinh, cong tan
hoc thien » hoc hien, hoc thieu, hoc thiet
trinh cua » trinh luat, trinh quan, trinh luan
cong manh » cong danh, duong manh, hoang manh
tinh cua » sinh cua, tinh chat, tranh cua
toan cao » toan ban, toan tap

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)) thong ((cong manh) OR (cong thanh)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien hach - hanh ((trinh cua) OR (tinh cua)) thong ((cong manh) OR (cong thanh)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thien hach - hanh ((trinh cua) or (tinh cua)) thong ((cong manh) OR (cong thanh)) toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc thien hach - hanh ((trinh cua) or (tinh cua)) thong ((cong manh) OR (cong thanh)) toan cao*.