Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
thuoc va » thuc va, thuoc ma, thuong va
cau tren » cu tren, dau tren, ca tren
hanh va » hang va, hanh vi
qua nam » quan nam, cua nam, quang nam
sac ky » cac ky, sai ky
tu sac » tu sach, tu cac, tu san
o hoi » co hoi, o hoc, o hai
x hoi » xa hoi, x ho, 5 hoi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang ((x hoi) OR (o hoi)). hieu qua nam thuoc va ((anh va) OR (hanh va)) cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky nang ((x hoi) OR (o hoi)). hieu qua nam thuoc va ((anh va) or (hanh va)) cau tren~".
• Adding a wildcard symbol may retrieve word variants: tu sac ky nang ((x hoi) OR (o hoi)). hieu qua nam thuoc va ((anh va) or (hanh va)) cau tren*.