Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
thanh ve » hanh ve, thanh va, thanh vien
truc vat » thuc vat, truc va, truc van
tu sach » thu sach, su sach, tu cach
cua tre » cuu tre, cua triet, dua tren
hieu va » lieu va, hieu qua
lang ha » long ha
ky lang » ky nang, ky dang, ky tang
te sach » toc sach
ha hoi » hoa hoi, ha noi, xa hoi
va cau » van cau, va cac, va dau
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (te sach)) ky lang ha hoi. hieu va cau truc vat thanh ve ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky lang ha hoi. hieu va cau truc vat thanh ve ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ky lang ha hoi. hieu va cau truc vat thanh ve ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky lang ha hoi. hieu va cau truc vat thanh ve ((cua tre) OR (cua te))*.