Perhaps you should try some spelling variations:
day nhanh » day thanh, duy nhanh, dac nhan
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
thuc day » thuc dan, thuc vat
nhanh va » hanh va, nhan va, nhanh ha
va triet » va trien, ve triet, cua triet
su sach » so sach, vu sach
nang ma » tang ma, sang ma, nang cao
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
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 y nang ma hoi. hieu van nam thuc day nhanh va ((va triet) or (va thiet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ma hoi. hieu van nam thuc day nhanh va ((va triet) OR (va thiet)).
• Adding a wildcard symbol may retrieve word variants: su sach y nang ma hoi. hieu van nam thuc day nhanh va ((va triet) or (va thiet))*.