Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
thuc day » thuc dan, thuc vat
nang doc » nang luc
danh va » doanh va, hanh va, anh va
thuc va » thuc vat, thuc dan
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
nang co » nang cao, nang noi, nang hoc
hieu va » lieu va, hieu qua
va cua » va chua, via cua, ca cua
va am » va lam, va cam

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 ty ((nang co) OR (nang doc)) hoi. hieu va am ((thuc va) or (thuc day)) danh va cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang co) OR (nang doc)) hoi. hieu va am ((thuc va) OR (thuc day)) danh va cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty ((nang co) OR (nang doc)) hoi. hieu va am ((thuc va) or (thuc day)) danh va cua triet*".