Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
cam thuc » am thuc, nam thuc, cam thu
hanh di » hanh vi, hanh de, hang di
sach ky » sac ky, sach ty, sach kem
hieu ve » hieu va
nang xa » nang x, lang xa, nang ma
di cua » dai cua, doi cua, de cua

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 ky) OR (sach y)) nang xa hoi. ((hieu ve) or (hieu van)) cam thuc van hanh di cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ky) OR (sach y)) nang xa hoi. ((hieu ve) OR (hieu van)) cam thuc van hanh di cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ky) OR (sach y)) nang xa hoi. ((hieu ve) or (hieu van)) cam thuc van hanh di cua triet*".