Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
nam thuoc » nam thuc, nam thu, nha thuoc
dau tieng » dau tien, cau tieng, day tieng
thuoc va » thuc va, thuoc ma, thuong va
tu sach » thu sach, su sach, te sach
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
va nam » van nam, ha nam, va nay
vi dau » vi dai, va dau, bi dau

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (thuoc sach)) ty nang xa hoi. hieu va nam thuoc va danh vi dau tieng~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thuoc sach)) ty nang xa hoi. hieu va nam thuoc va danh vi dau tieng.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thuoc sach)) ty nang xa hoi. hieu va nam thuoc va danh vi dau tieng*.