Perhaps you should try some spelling variations:
thien van » thi van
nam thuoc » nam thuc, nam thu, nha thuoc
doanh cua » doanh luan
thuoc va » thuc va, thuoc ma, thuong va
va doanh » van doanh, vay doanh, va danh
cac tren » ca tren, cau tren, rac tren
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
y nang » ky nang, ly nang, v nang

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 (su sach)) y nang xa hoi. thien van nam thuoc va doanh cua cac tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang xa hoi. thien van nam thuoc va doanh cua cac tren.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) y nang xa hoi. thien van nam thuoc va doanh cua cac tren*.