Perhaps you should try some spelling variations:
doc sach » hoc sach, toc sach, nuoc sach
va thanh » gia thanh, ban thanh, va tinh
ky sang » ky nang, ky dang, ky tang
ky danh » ky anh, ky dang
tao hoi » tao khoi, tao boi, tay hoi
lap cua » lai cua, tap cua, ap cua
lam cua » nam cua, lam chat
hieu v » hieu va, hieu ve, hieu 2
v pham » vi pham, d pham

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 ((ky sang) or (ky danh)) tao hoi. hieu v pham duc va thanh ((lap cua) OR (lam cua)) te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doc sach ((ky sang) OR (ky danh)) tao hoi. hieu v pham duc va thanh ((lap cua) OR (lam cua)) te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doc sach ((ky sang) or (ky danh)) tao hoi. hieu v pham duc va thanh ((lap cua) OR (lam cua)) te".
• Adding a wildcard symbol may retrieve word variants: doc sach ((ky sang) or (ky danh)) tao hoi. hieu v pham duc va thanh ((lap cua) OR (lam cua)) te*.