Perhaps you should try some spelling variations:
nuoc giao » nuoc giai, quoc gia, hoc giao
hoc sach » hoc sinh, hoc anh
thanh di » thanh doi, thanh de, thanh do
nuoc gia » nuoc giai, quoc gia, luoc gia
hieu va » lieu va, hieu qua
vu nang » vuc nang, va nang, vu dang
hoc cac » hoc cao
cua tre » cua te, cuu tre, cua triet
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: ((hoc sach) or (hoc cac)) vu nang x hoi. hieu va cac ((nuoc gia) OR (nuoc giao)) thanh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (hoc cac)) vu nang x hoi. hieu va cac ((nuoc gia) OR (nuoc giao)) thanh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc sach) or (hoc cac)) vu nang x hoi. hieu va cac ((nuoc gia) OR (nuoc giao)) thanh di cua tre".
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (hoc cac)) vu nang x hoi. hieu va cac ((nuoc gia) OR (nuoc giao)) thanh di cua tre*.