Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh vai » thanh hai, thanh van, thanh tai
cau tren » cu tren, dau tren, ca tren
nang mai » nang ma, nang tai, lang mai
cay lua » vay luan
vai cau » va cau, van cau, vai cac
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
mai hoi » mai khoi, dai hoi, lai hoi

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 ky nang mai hoi. ((hieu ve) or (lieu va)) ((cay lua) or (chay dua)) ban thanh vai cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang mai hoi. ((hieu ve) OR (lieu va)) ((cay lua) OR (chay dua)) ban thanh vai cau tren.
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang mai hoi. ((hieu ve) or (lieu va)) ((cay lua) or (chay dua)) ban thanh vai cau tren*.