Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh ve » hanh ve, thanh va, thanh vien
thuc gia » thuc giai, thue gia, thuc dia
nam thuc » nam thuoc, am thuc, nam thu
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
co sach » bo sach, cuon sach, hoc sach
ve nam » he nam, va nam, le nam
ma hoi » mai hoi, xa hoi, ma hoa
v nang » va nang, vu nang, van nang
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((su sach) or (co sach)) v nang ma hoi. hieu ve nam thuc gia thanh ve ((su triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (co sach)) v nang ma hoi. hieu ve nam thuc gia thanh ve ((su triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: ((su sach) or (co sach)) v nang ma hoi. hieu ve nam thuc gia thanh ve ((su triet) or (va thiet))*.