Perhaps you should try some spelling variations:
dau tien » van tien
dau tren » dat tren, dau tieng, dau trong
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
danh di » danh du, xanh di, danh dien
danh vi » hanh vi, dinh vi, danh va
te sach » toc sach
nang co » nang cao, nang doc, nang noi
nam xua » nam cua, nam mua, nam qua
xua va » xuat va, vua va, sua va
co loi » co hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang co loi. hieu van nam xua va ((danh vi) or (danh di)) ((dau tren) OR (dau tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang co loi. hieu van nam xua va ((danh vi) OR (danh di)) ((dau tren) OR (dau tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang co loi. hieu van nam xua va ((danh vi) or (danh di)) ((dau tren) OR (dau tien))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang co loi. hieu van nam xua va ((danh vi) or (danh di)) ((dau tren) OR (dau tien))*.