Perhaps you should try some spelling variations:
nam thuoc » nam thuc, nam thu, nha thuoc
cua viet » ca viet, hoa viet, cua vat
sach thi » sach thu, sach tai, sach thieu
thi hang » thi hanh, thi nang, thi hong
hanh vai » hanh vi, hanh tai, hanh van
thuoc va » thuc va, thuoc ma, thuong va
hanh va » hang va, hanh vi
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
hieu ve » hieu van
hang xa » hoang xa, hang va, hang ca

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 thi hang xa hoi. ((hieu ve) OR (hieu va)) nam thuoc va ((hanh vai) or (hanh va)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach thi hang xa hoi. ((hieu ve) OR (hieu va)) nam thuoc va ((hanh vai) OR (hanh va)) cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach thi hang xa hoi. ((hieu ve) OR (hieu va)) nam thuoc va ((hanh vai) or (hanh va)) cua viet".
• Adding a wildcard symbol may retrieve word variants: su sach thi hang xa hoi. ((hieu ve) OR (hieu va)) nam thuoc va ((hanh vai) or (hanh va)) cua viet*.