Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
phong cong » phong chong, thong cong, chong cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
trinh cua » trinh luat, trinh quan, trinh luan
tinh cua » sinh cua, tinh chat, tranh cua
cong dan » cong san, cong tan, huong dan
than man » than ma, tran manh, than phan

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thiet tach - hanh ((trinh cua) OR (tinh cua)) phong cong dan ((than man) or (thanh san))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - hanh ((trinh cua) OR (tinh cua)) phong cong dan ((than man) OR (thanh san)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - hanh ((trinh cua) OR (tinh cua)) phong cong dan ((than man) or (thanh san))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - hanh ((trinh cua) OR (tinh cua)) phong cong dan ((than man) or (thanh san))*.