Perhaps you should try some spelling variations:
thien van » thi van
sach ty » sach y, sach tu, sach thu
thuc va » thuc vat, thuc dan, thuc day
thuc ma » thuoc ma, thuc ha, thuc vat
te sach » toc sach
hieu va » lieu va, hieu qua
nang co » nang cao, nang doc, nang noi
ty nang » ky nang, ty xang, ty hang
cuu tre » cua tre, cau tren, cau treo
co hoi » co hoc, co loi
vi cuu » vi luu, vinh cuu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty nang co hoi. ((hieu va) OR (thien van)) nhan ((thuc ma) OR (thuc va)) hanh vi cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ty nang co hoi. ((hieu va) or (thien van)) nhan ((thuc ma) OR (thuc va)) hanh vi cuu tre~".
• Adding a wildcard symbol may retrieve word variants: te sach ty nang co hoi. ((hieu va) or (thien van)) nhan ((thuc ma) OR (thuc va)) hanh vi cuu tre*.