Perhaps you should try some spelling variations:
hanh hanh » hanh han, xanh hanh, nhanh thanh
hanh doi » thanh doi, hanh noi, hang doi
su sach » so sach, vu sach
doi cua » dai cua, hoi cua
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
lang xa » lang ha, dang xay, lang van
tang ma » mang may, tang van
am thu » am thuc, cam thu, am phu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y ((lang xa) or (tang ma)) hoi. hieu ve ((am thu) OR (nam thu)) hanh hanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y ((lang xa) OR (tang ma)) hoi. hieu ve ((am thu) OR (nam thu)) hanh hanh doi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y ((lang xa) or (tang ma)) hoi. hieu ve ((am thu) OR (nam thu)) hanh hanh doi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach y ((lang xa) or (tang ma)) hoi. hieu ve ((am thu) OR (nam thu)) hanh hanh doi cua tre*.