Perhaps you should try some spelling variations:
sang nhung » song nhung, dang hung, bang chung
chieu tinh » trieu tinh, lieu tinh, chau tinh
hieu manh » chieu xanh, hieu nganh, dieu hanh
tranh cua » doanh cua, manh cua
nhung tap » nhung bai, nhung cau, chung ta
cua sang » cua dang, cua hang, cua san
tap toan » tap doan, tap quan, bai toan
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc ((hieu manh) or (chieu tinh)) - canh tranh cua sang nhung tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc ((hieu manh) OR (chieu tinh)) - canh tranh cua sang nhung tap toan cao.
• Adding a wildcard symbol may retrieve word variants: doc ((hieu manh) or (chieu tinh)) - canh tranh cua sang nhung tap toan cao*.