Perhaps you should try some spelling variations:
vanh dai » van dai, vanh tai, lanh dao
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
ky lang » ky nang, ky dang, tay lang
ky tang » ky nang, ky dang, kho tang
hieu va » lieu va, hieu qua
va vanh » va van, va danh, va hanh
cua tre » cua te, cuu tre, cua triet
va cam » va cham, va cac, va cao
xuc va » duc va, tuc va, luc va

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 (su sach)) ((ky lang) OR (ky tang)) xa hoi. hieu va cam xuc va vanh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ((ky lang) OR (ky tang)) xa hoi. hieu va cam xuc va vanh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ((ky lang) OR (ky tang)) xa hoi. hieu va cam xuc va vanh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ((ky lang) OR (ky tang)) xa hoi. hieu va cam xuc va vanh dai cua tre*.