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

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: ((tu sach) OR (te sach)) ((ky lang) OR (ky dang)) ha hoi. hieu va cau truc vat thanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (te sach)) ((ky lang) OR (ky dang)) ha hoi. hieu va cau truc vat thanh vi cua tre~".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ((ky lang) OR (ky dang)) ha hoi. hieu va cau truc vat thanh vi cua tre*.