Perhaps you should try some spelling variations:
chieu sach » chinh sach, chiet tach, chieu xanh
chieu sang » chieu xanh, hieu lang, nhieu tang
trinh dan » trinh han, trinh san, trinh da
thuc hung » thuc chung, thuc nhung, thuc dung
hung cong » nhung cong, hung cuong, phung cong
cong toan » cong tan, cong hoan, cong tuan
toan phan » thanh phan, toan ban, hoa phan
tinh dan » tinh da, binh dan, tinh dau
phan dau » phan tu, hang 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 ((chieu sach) or (chieu sang)) - ((tinh dan) OR (trinh dan)) thuc hung cong toan phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((chieu sach) OR (chieu sang)) - ((tinh dan) OR (trinh dan)) thuc hung cong toan phan dau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((chieu sach) or (chieu sang)) - ((tinh dan) OR (trinh dan)) thuc hung cong toan phan dau".
• Adding a wildcard symbol may retrieve word variants: hoc ((chieu sach) or (chieu sang)) - ((tinh dan) OR (trinh dan)) thuc hung cong toan phan dau*.