Perhaps you should try some spelling variations:
thien van » thi van
thu sach » tu sach, thuat sach, thuoc sach
lam thuc » lam thuoc, am thuc, nam thuc
thuc va » thuc vat, thuc dan, thuc day
hieu ve » hieu va, hieu van
dan vi » doan vi, don vi, dan va
va dan » ca dan, va dao, va dau
vi luu » vi lua
y nang » ky nang, ly nang, v nang
o hoc » co hoc, mo hoc, so hoc
o hoi » co hoi, o hai, o hoa
tru » truc

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach y nang ((o hoi) or (o hoc)). ((hieu ve) or (thien van)) lam thuc va dan vi luu tru~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang ((o hoi) OR (o hoc)). ((hieu ve) OR (thien van)) lam thuc va dan vi luu tru.
• Adding a wildcard symbol may retrieve word variants: thu sach y nang ((o hoi) or (o hoc)). ((hieu ve) or (thien van)) lam thuc va dan vi luu tru*.