Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
cua triet » cua viet, su triet, va triet
sach han » sach tham, sach danh, sach nang
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
sinh dai » sinh thai, si dai, sinh vat
te sach » toc sach
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
thuc va » thuc vat, thuc dan, thuc day
va sinh » va kinh, va tinh, vi sinh

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 han ((nang ma) OR (sang ma)) hoi. hieu van cham thuc va sinh dai cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach han ((nang ma) OR (sang ma)) hoi. hieu van cham thuc va sinh dai cua triet".
• Adding a wildcard symbol may retrieve word variants: te sach han ((nang ma) OR (sang ma)) hoi. hieu van cham thuc va sinh dai cua triet*.