Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
cham tuc » pham thuc, tham thuc, cham soc
cuu tre » cua tre, cau tren, cau treo
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi
ky sang » ky nang, ky dang, ky tang
sac ky » cac ky, sai ky
ma hoi » xa hoi, ma hoa, me hoi
va don » va dong, va doc, va do
vi cuu » vi luu, vinh cuu
tu sac » tu sach, tu cac, tu san

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

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky sang ((ma hoi) OR (mai hoi)). hieu ve ((cham tuc) OR (nham thuc)) va don vi cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky sang ((ma hoi) OR (mai hoi)). hieu ve ((cham tuc) or (nham thuc)) va don vi cuu tre~".
• Adding a wildcard symbol may retrieve word variants: tu sac ky sang ((ma hoi) OR (mai hoi)). hieu ve ((cham tuc) or (nham thuc)) va don vi cuu tre*.