Perhaps you should try some spelling variations:
hanh hai » thanh hai, nhanh hai, hang hai
van hanh » van thanh, ban hanh, van anh
so sach » so sanh, bo sach, co sach
ve chao » ve chat, ve cham, ve chang
hai cua » thai cua, dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet
ve cho » ve co, ve che, de cho
vu van » tu van
o lang » hoa lang, hoi lang

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

• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ((_ lang) OR (o lang)) xa hoi. hieu ((ve chao) OR (ve cho)) vu van hanh hai cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ((_ lang) or (o lang)) xa hoi. hieu ((ve chao) OR (ve cho)) vu van hanh hai cua tre~".
• Adding a wildcard symbol may retrieve word variants: so sach ((_ lang) or (o lang)) xa hoi. hieu ((ve chao) OR (ve cho)) vu van hanh hai cua tre*.