Perhaps you should try some spelling variations:
te sach » toc sach
son hai » cong hai
hieu va » lieu va, hieu qua
xuc ban » cuc ban, quoc ban, xuat ban
duc ban » duc tan, duc van, dua ban
anh dai » vanh dai, anh bai, anh dat
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
va cam » va cham, va cac, va cao

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((y nang) OR (v nang)) son hai. hieu va cam ((xuc ban) or (duc ban)) anh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((y nang) OR (v nang)) son hai. hieu va cam ((xuc ban) OR (duc ban)) anh dai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((y nang) OR (v nang)) son hai. hieu va cam ((xuc ban) or (duc ban)) anh dai cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((y nang) OR (v nang)) son hai. hieu va cam ((xuc ban) or (duc ban)) anh dai cua tre*.