Perhaps you should try some spelling variations:
vanh dai » vanh tai, lanh dao, van dao
tu sach » thu sach, su sach, te sach
ky lang » ky nang, ky dang, tay lang
ky tang » ky nang, ky dang, kho tang
hieu va » lieu va, hieu qua
van dai » van dao, van hai, can dai
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 ((ky lang) or (ky tang)) xa hoi. hieu va cam xuc va ((vanh dai) OR (van dai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky lang) OR (ky tang)) xa hoi. hieu va cam xuc va ((vanh dai) OR (van dai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky lang) or (ky tang)) xa hoi. hieu va cam xuc va ((vanh dai) OR (van dai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky lang) or (ky tang)) xa hoi. hieu va cam xuc va ((vanh dai) OR (van dai)) cua tre*.