Perhaps you should try some spelling variations:
nhung cong » dung cong, thong cong, hang cong
chau tinh » cuu tinh, cua tinh, cac tinh
trang va » tran van
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan cao » toan ban, toan tap
ha tinh » va tinh, may tinh

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((chau tinh) or (ha tinh)) - hanh ((trang va) OR (hang va)) nhung cong tan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chau tinh) OR (ha tinh)) - hanh ((trang va) OR (hang va)) nhung cong tan toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chau tinh) or (ha tinh)) - hanh ((trang va) OR (hang va)) nhung cong tan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((chau tinh) or (ha tinh)) - hanh ((trang va) OR (hang va)) nhung cong tan toan cao*.