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

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

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