Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
cau tren » cu tren, dau tren, ca tren
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
cau luc » cau truc, cau phuc
danh vi » hanh vi, dinh vi, danh va
danh di » danh du, xanh di, danh dien
ma hoi » xa hoi, ma hoa, me hoi
luc va » duc va, tuc va, loc va
ve cau » ke cau, va cau, ve cac

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sach ky nang ((ma hoi) or (mai hoi)). hieu ve cau luc va ((danh vi) OR (danh di)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sach ky nang ((ma hoi) OR (mai hoi)). hieu ve cau luc va ((danh vi) OR (danh di)) cau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc sach ky nang ((ma hoi) or (mai hoi)). hieu ve cau luc va ((danh vi) OR (danh di)) cau tren".
• Adding a wildcard symbol may retrieve word variants: hoc sach ky nang ((ma hoi) or (mai hoi)). hieu ve cau luc va ((danh vi) OR (danh di)) cau tren*.