Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
thu sach » tu sach, thuat sach, thuoc sach
dinh di » dinh du, dinh vi, danh di
va dinh » van dinh, va kinh, va tinh
tu cach » tu cac
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, tuc va, luc va
di cua » dai cua, doi cua, de cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (thu sach)) ky tang xa hoi. ((hieu van) OR (thien van)) cam xuc va dinh di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) ky tang xa hoi. ((hieu van) OR (thien van)) cam xuc va dinh di cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thu sach)) ky tang xa hoi. ((hieu van) OR (thien van)) cam xuc va dinh di cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thu sach)) ky tang xa hoi. ((hieu van) OR (thien van)) cam xuc va dinh di cua tre*.