Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » thien van, lieu va, hieu ve
anh giau » anh giao, canh giac, anh giang
giau cua » gian cua, gia cua, dieu cua
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
van anh » van thanh, tuan anh, van minh
cua tre » cua te, cuu tre, cua triet
cau lo » cau do, cau o, cam lo
lo van » le van, vo van, so van
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 ky nang ((x hoi) or (x ho)). ((hieu van) OR (hieu va)) cau lo van anh giau cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ky nang ((x hoi) OR (x ho)). ((hieu van) OR (hieu va)) cau lo van anh giau cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuoc sach ky nang ((x hoi) or (x ho)). ((hieu van) OR (hieu va)) cau lo van anh giau cua tre".
• Adding a wildcard symbol may retrieve word variants: thuoc sach ky nang ((x hoi) or (x ho)). ((hieu van) OR (hieu va)) cau lo van anh giau cua tre*.