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

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 hoi. hieu van nam xua va ((danh vi) OR (hanh vi)) ((dau tieng) or (dau tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang co hoi. hieu van nam xua va ((danh vi) OR (hanh vi)) ((dau tieng) OR (dau tien))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang co hoi. hieu van nam xua va ((danh vi) OR (hanh vi)) ((dau tieng) or (dau tien))*".