Perhaps you should try some spelling variations:
cua triet » su triet, va triet
cua viet » ca viet, hoa viet, cua vat
cam thuc » am thuc, nam thuc, cam thu
ban hanh » ban hang
sach van » sach han, sach va, bach van
thuc ban » thuoc ban, thuc dan, thu ban
hieu van » hieu va, thien van, lieu va
van nang » van quang, van ban, van dong
van cam » van nam, van lam, van cau
hanh de » hanh ve, hanh kem
cua tre » cua te, cuu tre, dua tren
su sach » so sach, vu sach
nang o » nang co, nang ho, nang ro
o hoi » co hoi, o hoc, o hai

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 van nang o hoi. hieu van cam thuc ban hanh de ((cua tre) or (((cua triet) OR (cua viet))))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach van nang o hoi. hieu van cam thuc ban hanh de ((cua tre) OR (((cua triet) OR (cua viet)))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach van nang o hoi. hieu van cam thuc ban hanh de ((cua tre) or (((cua triet) OR (cua viet))))".
• Adding a wildcard symbol may retrieve word variants: su sach van nang o hoi. hieu van cam thuc ban hanh de ((cua tre) or (((cua triet) OR (cua viet))))*.