Perhaps you should try some spelling variations:
xanh hanh » danh thanh, ban hanh, van hanh
thu xanh » thu canh, thu anh, thu oanh
so sach » so sanh, bo sach, co sach
hanh de » hanh ve, hanh kem
cam thu » nam thu, cac thu, ca thu
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
vu sach » vu bach, su sach, vu khach
va cam » va cham, va cac, va cao
y nang » ky nang, ly nang, v nang
de cua » le cua, te cua, dieu cua
o hoi » co hoi, o hai, o hoa
o hoc » co hoc, mo hoc, so hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (vu sach)) y nang ((o hoi) or (o hoc)). hieu va cam thu xanh hanh de cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (vu sach)) y nang ((o hoi) OR (o hoc)). hieu va cam thu xanh hanh de cua tre.
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (vu sach)) y nang ((o hoi) or (o hoc)). hieu va cam thu xanh hanh de cua tre*.