Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
tham thuc » nham thuc, pham thuc, tam thuc
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
hoc anh » hoc nganh, hoc nhanh, ngoc anh
hieu ve » hieu va, hieu van
ve tham » va tham, ve cham, vi tham
ca viet » va viet, co viet, hoa viet
x hoi » o hoi, x ho, 5 hoi
vi ca » vit ca, li ca, va ca

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 (hoc anh)) ky nang ((x hoi) or (xa hoi)). hieu ve tham thuc dan hanh vi ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thuoc sach) OR (hoc anh)) ky nang ((x hoi) OR (xa hoi)). hieu ve tham thuc dan hanh vi ca viet.
• Adding a wildcard symbol may retrieve word variants: ((thuoc sach) or (hoc anh)) ky nang ((x hoi) or (xa hoi)). hieu ve tham thuc dan hanh vi ca viet*.