Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
dinh vi » dinh ve, dinh viet, dinh tri
danh vi » hanh vi, danh di, danh va
cau luc » cau truc, cau phuc
ky sang » ky nang, ky dang, ky tang
sinh ky » sinh ly, sinh y, kinh ky
sang ma » tang ma, nang ma, sang tao
hieu ve » hieu va
luc va » duc va, tuc va, loc va
ma hoi » mai hoi, xa hoi, ma hoa

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

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