Perhaps you should try some spelling variations:
hieu van » thien van, lieu va
cam thuc » am thuc, nam thuc, cam thu
thuc day » thuc dan, thuc vat
day hanh » day nhanh, day thanh, dao hanh
va triet » va thiet, va trien, ve triet
su sach » so sach, vu sach
hieu va » lieu va, hieu qua
hanh di » hanh vi, hanh de, hang di
y nang » ky nang, ly nang, v nang
x hoi » xa hoi, o hoi, x ho
di va » dai va, di vao, doi va

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 x hoi. ((((hieu ve) or (hieu van))) or (hieu va)) cam thuc day hanh di va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang x hoi. ((((hieu ve) OR (hieu van))) OR (hieu va)) cam thuc day hanh di va triet.
• Adding a wildcard symbol may retrieve word variants: su sach y nang x hoi. ((((hieu ve) or (hieu van))) or (hieu va)) cam thuc day hanh di va triet*.