Perhaps you should try some spelling variations:
thieu sach » chieu sach, hieu cach, theo sach
thien hach » thien thanh, hien hanh
hanh tang » hanh trang, anh tang, hanh mang
bang song » nang song
song tinh » cong tinh, long tinh, dong tinh
tang cua » mang cua, hang cua, tang luan
cua bang » chua bang, cua ban, cua dang
toan cau » toan cao, toan ban, toan tai
toan tap » toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((thieu sach) or (thien hach)) - hanh tang cua bang song tinh ((toan cau) OR (toan tap))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu sach) OR (thien hach)) - hanh tang cua bang song tinh ((toan cau) OR (toan tap)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu sach) or (thien hach)) - hanh tang cua bang song tinh ((toan cau) OR (toan tap))".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu sach) or (thien hach)) - hanh tang cua bang song tinh ((toan cau) OR (toan tap))*.