Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
thanh vai » thanh hai, thanh tai, thanh oai
thu sach » thuat sach, thuoc sach, thu hoach
tu sach » su sach, te sach, tu cach
qua ban » cua ban, qua quan
bay qua » cay qua, ban quan, bao quan
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
va bay » van bay, va bai, va bao

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 (thu sach)) ky nang ma hoa. hieu va bay qua ban ((thanh vai) or (thanh van)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky nang ma hoa. hieu va bay qua ban ((thanh vai) OR (thanh van)) cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (thu sach)) ky nang ma hoa. hieu va bay qua ban ((thanh vai) or (thanh van)) cua tre*".