Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh hai » thanh phan, thanh hoa, thanh san
van giao » nang giao, toan giao, dan gian
tu sach » thu sach, su sach, te sach
va giao » va giai, va gia, ve giao
dua ban » dia ban, cua ban, qua ban
hai cuu » hai cua, hai chu, hai cuc
cuu tre » cua tre, cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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 hoach)) ky nang x hoi. hieu ((va giao) OR (van giao)) dua ban thanh hai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky nang x hoi. hieu ((va giao) OR (van giao)) dua ban thanh hai cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu hoach)) ky nang x hoi. hieu ((va giao) OR (van giao)) dua ban thanh hai cuu tre*".