Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
vat hanh » vat thanh, van hanh, va hanh
ban hanh » ban hang
so sach » so sanh, bo sach, co sach
van cam » van nam, van lam, van cau
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho

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 y nang x hoi. hieu van cam thuc ((vat hanh) or (ban hanh)) doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach y nang x hoi. hieu van cam thuc ((vat hanh) OR (ban hanh)) doi cua tre.
• Adding a wildcard symbol may retrieve word variants: so sach y nang x hoi. hieu van cam thuc ((vat hanh) or (ban hanh)) doi cua tre*.