Perhaps you should try some spelling variations:
thieu sach » chieu sach, thien hach, hieu cach
duong manh » duong van
hoc thieu » toc thieu, hoc hien
quang cua » quan cua, quang tuan, quang huy
cua nhung » va nhung
cong manh » cong danh, cong thanh, hoang manh
toan cau » 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: hoc thieu sach - nhanh quang cua nhung ((cong manh) or (duong manh)) toan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sach - nhanh quang cua nhung ((cong manh) OR (duong manh)) toan cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu sach - nhanh quang cua nhung ((cong manh) or (duong manh)) toan cau*.