Perhaps you should try some spelling variations:
luat duoc » luat tuc
dat duoc » dat nuoc, da duoc, xuat duoc
cua tre » cua te, cuu tre, cua triet
va hanh » van hanh, va thanh, ban hanh
ky tang » ky nang, ky dang, kho tang
tang ma » mang may, tang van
hieu ve » hieu va, hieu van
va danh » va dinh, va dan, dia danh
di cua » dai cua, doi cua, de cua
vu ban » tu ban, va ban
ban ky » van ky, dan ky
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: vu ban ky tang ma hoi. hieu ve ((dat duoc) OR (luat duoc)) ((va hanh) or (va danh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ban ky tang ma hoi. hieu ve ((dat duoc) OR (luat duoc)) ((va hanh) OR (va danh)) di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ban ky tang ma hoi. hieu ve ((dat duoc) OR (luat duoc)) ((va hanh) or (va danh)) di cua tre*".