Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cam thuc » am thuc, nam thuc, cam thu
thanh va » thanh van, hanh va, thanh ha
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
hieu ve » hieu va
sach ky » sac ky, sach y, sach ty
thuc va » thuc vat, thuc dan, thuc day
dang ha » dong ha, dung ha, lang ha
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, dua tren
te sach » toc sach
ha hoi » hoa hoi, ha noi, xa hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky dang ha hoi. ((hieu ve) OR (hieu van)) cam thuc va thanh va ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky dang ha hoi. ((hieu ve) OR (hieu van)) cam thuc va thanh va ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky dang ha hoi. ((hieu ve) OR (hieu van)) cam thuc va thanh va ((cua tre) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: te sach ky dang ha hoi. ((hieu ve) OR (hieu van)) cam thuc va thanh va ((cua tre) or (cua triet))*.