Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
thanh tung » thanh cong
hoc thiet » hoc thieu, hoc thuyet, hoc hien
cap phan » cac phan, cao phan, cau phan
dan phan » doan phan, van phan, dam phan
dan chan » dan gian, dan ca, van chat
cap han » cap can, cap hay, cap 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 thiet tach - thanh tung ((cap han) or (cap phan)) cong ((dan phan) OR (dan chan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - thanh tung ((cap han) OR (cap phan)) cong ((dan phan) OR (dan chan)) cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - thanh tung ((cap han) or (cap phan)) cong ((dan phan) OR (dan chan)) cau".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - thanh tung ((cap han) or (cap phan)) cong ((dan phan) OR (dan chan)) cau*.