Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
thanh ha » thanh hoa, thanh hai, nhanh ha
xuc gia » duc gia, luc gia, tuc gia
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
va cam » va cham, va cac, va cai
va cao » va cac, va co, va dao
ha cuu » ho cuu, cham cuu, khao cuu
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: doc sach y nang x hoi. hieu ((va cam) OR (va cao)) ((xuc gia) or (quoc gia)) thanh ha cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach y nang x hoi. hieu ((va cam) OR (va cao)) ((xuc gia) OR (quoc gia)) thanh ha cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach y nang x hoi. hieu ((va cam) OR (va cao)) ((xuc gia) or (quoc gia)) thanh ha cuu tre*".