Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
phan xuong » phan cong
xuong cong » luong cong, duong cong, cuong cong
cong thanh » dong thanh, cong trinh, cong tan
hoc thiet » hoc thieu, hoc thuyet, hoc hien
hanh dung » thanh dung, anh dung, hanh dong
dung phan » dung nhan, dung luan, dung ha
thanh lap » thanh san, thanh hai, thanh van
toan lap » toan tap, toan lao, toan ban
phan lap » phan dau

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 dung phan xuong cong thanh ((toan lap) or (((thanh lap) OR (phan lap))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - hanh dung phan xuong cong thanh ((toan lap) OR (((thanh lap) OR (phan lap)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - hanh dung phan xuong cong thanh ((toan lap) or (((thanh lap) OR (phan lap))))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - hanh dung phan xuong cong thanh ((toan lap) or (((thanh lap) OR (phan lap))))*.