Perhaps you should try some spelling variations:
lam truc » lam truoc, nam truc, lam thuoc
hieu van » hieu va, thien van, lieu va
danh di » danh du, xanh di, danh dien
danh vi » hanh vi, dinh vi, danh va
truc va » thuc va, thuc vat, trung va
van lam » van nam
sach ly » sach y, sach lo, sach hay
lang xa » lang ha, dang xay, lang van
sach ty » sach y, sach tu, sach thu
cua tre » cua te, cuu tre, cua triet

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 ly) or (sach ty)) lang xa hoi. hieu van lam truc va ((danh vi) OR (danh di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ly) OR (sach ty)) lang xa hoi. hieu van lam truc va ((danh vi) OR (danh di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ly) or (sach ty)) lang xa hoi. hieu van lam truc va ((danh vi) OR (danh di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach ly) or (sach ty)) lang xa hoi. hieu van lam truc va ((danh vi) OR (danh di)) cua tre*.