Perhaps you should try some spelling variations:
sach loai » sach bai, cac loai, sach doi
loai nang » loai nam, luan nang, loai san
nam thuc » nam thuoc, am thuc, nam thu
cua viet » hoa viet, cua vat, cua dieu
day hanh » day nhanh, day thanh, dao hanh
thuc day » thuc dan, thuc vat
hanh di » hanh vi, hanh de, hang di
tu sach » thu sach, su sach, te sach
hieu va » hieu qua
nang xa » nang x, lang xa, nang ma
ca viet » va viet, co viet, hoa viet

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 sach loai nang xa hoi. ((lieu va) OR (hieu va)) nam thuc day hanh di ((cua viet) OR (ca viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach loai nang xa hoi. ((lieu va) or (hieu va)) nam thuc day hanh di ((cua viet) OR (ca viet))~".
• Adding a wildcard symbol may retrieve word variants: tu sach loai nang xa hoi. ((lieu va) or (hieu va)) nam thuc day hanh di ((cua viet) OR (ca viet))*.