Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thanh giau » thanh gian, thanh giang, thanh lieu
thien van » thi van
van thanh » ban thanh, van tuan
cau tren » cu tren, dau tren, ca tren
van bac » van ban, van bao, van hac
cua tre » cua te, cuu tre, cua triet
y nang » ly nang, v nang, may nang
bac vo » bac bo, bac ho, bac va
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: thuoc sach ((y nang) OR (ky nang)) x hoi. thien van bac vo van thanh giau ((cua tre) or (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((y nang) OR (ky nang)) x hoi. thien van bac vo van thanh giau ((cua tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ((y nang) OR (ky nang)) x hoi. thien van bac vo van thanh giau ((cua tre) or (cau tren))".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((y nang) OR (ky nang)) x hoi. thien van bac vo van thanh giau ((cua tre) or (cau tren))*.