Perhaps you should try some spelling variations:
cau tren » dau tren, ca tren, cau treo
hoc anh » hoc nganh, hoc nhanh, ngoc anh
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
cau luc » cau truc, cau phuc
hieu ve » hieu va, hieu van
cu tren » tu tren, dua tren
mai hoi » mai khoi, dai hoi, lai hoi
luc va » duc va, tuc va, loc va
ma hoi » xa hoi, ma hoa, me hoi
ve cau » ke cau, va cau, ve cac
anh 6 » anh d, anh _, anh y

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc anh 6 tang ((ma hoi) or (mai hoi)). hieu ve cau luc va danh vi ((cau tren) OR (cu tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc anh 6 tang ((ma hoi) OR (mai hoi)). hieu ve cau luc va danh vi ((cau tren) OR (cu tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc anh 6 tang ((ma hoi) or (mai hoi)). hieu ve cau luc va danh vi ((cau tren) OR (cu tren))".
• Adding a wildcard symbol may retrieve word variants: hoc anh 6 tang ((ma hoi) or (mai hoi)). hieu ve cau luc va danh vi ((cau tren) OR (cu tren))*.