Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
hanh tai » thanh tai, hang tai, han tai
cua viet » ca viet, hoa viet, cua vat
su sach » so sach, vu sach
ky sang » ky nang, ky dang, ky tang
sang xa » song xa, lang xa, sang ma
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tai cuc, tri cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (thuoc sach)) ky sang xa hoi. hieu van nam thuc va hanh tai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (thuoc sach)) ky sang xa hoi. hieu van nam thuc va hanh tai cua viet.
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (thuoc sach)) ky sang xa hoi. hieu van nam thuc va hanh tai cua viet*.