Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
thuc day » thuc dan, thuc vat
nam thuc » nam thuoc, am thuc, nam thu
nang ha » nang hai, nang han, nang hoa
dinh va » dinh van, dinh ve, dinh ba
sinh va » sinh vat, dinh van
tinh va » tich va, trinh van, trinh vat
ha hoi » hoa hoi, ha noi, xa hoi
sac ky » cac ky, sai ky
te sac » te sach, te cac, te san

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky nang ha hoi. hieu van nam thuc day ((((dinh va) OR (sinh va))) or (tinh va)) cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky nang ha hoi. hieu van nam thuc day ((((dinh va) OR (sinh va))) OR (tinh va)) cau tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky nang ha hoi. hieu van nam thuc day ((((dinh va) OR (sinh va))) or (tinh va)) cau tren*".