Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuoc sinh
thuat sach » thuat lanh, thuat san
hieu van » hieu va, thien van, lieu va
tinh ve » trinh ve, tinh ven, dinh ve
va tinh » may tinh
lam xuc » cam xuc, lam duoc
van lam » van nam
tu sach » thu sach, su sach, te sach
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
ve cua » le cua, de cua, te 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 sach) or (((thuoc sach) OR (thuat sach)))) ky tang xa hoi. hieu van lam xuc va tinh ve cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (((thuoc sach) OR (thuat sach)))) ky tang xa hoi. hieu van lam xuc va tinh ve cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (((thuoc sach) OR (thuat sach)))) ky tang xa hoi. hieu van lam xuc va tinh ve cua tre".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (((thuoc sach) OR (thuat sach)))) ky tang xa hoi. hieu van lam xuc va tinh ve cua tre*.