Perhaps you should try some spelling variations:
ban hanh » ban hang
tang mai » tang ma, tang tai, lang mai
vien cac » vien bach, vien dai, vien da
tu sach » thu sach, su sach, te sach
cuu tre » cua tre, cau tren, cau treo
mai hoi » mai khoi, dai hoi, lai hoi
ve cai » ve cac, ve tai, ve cau
sach 7 » sach y, sach 2
va cai » va cac, va bai, va dai
tu ban » thu ban, te ban
7 tang » 6 tang
vi cuu » vi luu, vinh cuu

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 7 tang mai hoi. hieu ((((ve cai) OR (va cai))) OR (vien cac)) tu ban hanh vi cuu tre~.
• Adding a wildcard symbol may retrieve word variants: tu sach 7 tang mai hoi. hieu ((((ve cai) or (va cai))) or (vien cac)) tu ban hanh vi cuu tre*.