Perhaps you should try some spelling variations:
thuoc sach » hoc sach, thuat sach, thuoc sinh
nuoc sach » nguoi sach, hoc sach, cuoc cach
dang thai » dang thi, dang hai, dang khai
bac nuoc » cac nuoc, bach tuoc, sach nuoc
nuoc san » nuoc luan, nguoi san, nuoc quan
san dang » van dang, san sang, ban dang
thai cua » than cua, tai cuc, tri cua
thi van » thi lan, thi hanh, thi nang
van bac » van ban, van bao, van hac
cua tre » cua te, cuu tre, cua triet
x hoi » xa hoi, o hoi, 5 hoi

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) OR (nuoc sach)) ky nang ((x hoi) or (x ho)). thi van bac nuoc san dang thai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (nuoc sach)) ky nang ((x hoi) OR (x ho)). thi van bac nuoc san dang thai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thuoc sach) OR (nuoc sach)) ky nang ((x hoi) or (x ho)). thi van bac nuoc san dang thai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) OR (nuoc sach)) ky nang ((x hoi) or (x ho)). thi van bac nuoc san dang thai cua tre*.