Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
cham thuc » pham thuc, tham thuc, pham thuoc
su hien » su kien, thu hien, nhu hien
sach ky » sac ky, sach y, sach ty
te sach » toc sach
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
su tien » su kien, tu tieng, dau tien
va dat » va dao, va dau, va dap
dat vi » dat va, hat vi, dat ve

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky lang xa hoi. hieu ve ((cham thuc) or (nham thuc)) va dat vi ((su hien) OR (su tien))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. hieu ve ((cham thuc) OR (nham thuc)) va dat vi ((su hien) OR (su tien)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang xa hoi. hieu ve ((cham thuc) or (nham thuc)) va dat vi ((su hien) OR (su tien))".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. hieu ve ((cham thuc) or (nham thuc)) va dat vi ((su hien) OR (su tien))*.