Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
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
hanh dai » hanh tai, hanh dao, vanh dai
su sach » so sach, vu sach
sach ly » sach y, sach lo, sach ty
ly nang » ky nang, ly hang, ly vang
hieu va » lieu va, hieu qua
x hoi » xa hoi, o hoi, x ho

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