Perhaps you should try some spelling variations:
thanh trung » thanh tung
thiet tach » thien hach, thuat tach
chiet tach » chieu sach
nhung lang » nhanh lang, nhung cong
trung van » truong van, trong van, trung va
nhung van » phung van, nhung bai, nhung cau
van tuan » van quan, van ban, anh tuan
tuan cau » toan cau, quan cau, tuan cu

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) or (chiet tach)) - thanh trung van ((nhung lang) OR (nhung van)) van tuan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thiet tach) OR (chiet tach)) - thanh trung van ((nhung lang) OR (nhung van)) van tuan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thiet tach) or (chiet tach)) - thanh trung van ((nhung lang) OR (nhung van)) van tuan cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((thiet tach) or (chiet tach)) - thanh trung van ((nhung lang) OR (nhung van)) van tuan cau*.