Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
hanh di » hanh vi, hanh de, hang di
tu sach » thu sach, su sach, te sach
van cam » van nam, van lam, van cau
so sach » so sanh, bo sach, co sach
y nang » ky nang, ly nang, v nang
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa
di cua » dai cua, doi cua, de cua
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: ((tu sach) or (so sach)) y nang x hoi. hieu van cam ((xuc va) or (tuc va)) hanh di cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (so sach)) y nang x hoi. hieu van cam ((xuc va) OR (tuc va)) hanh di cua viet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (so sach)) y nang x hoi. hieu van cam ((xuc va) or (tuc va)) hanh di cua viet*.