Perhaps you should try some spelling variations:
ban trinh » ban tinh, dan trinh, van trinh
trinh vat » trinh van, trinh luat, sinh vat
dang xay » dang van, van xay
cach cua » mach cua, cac cua, cach dua
cau tren » cu tren, dau tren, ca tren
tu sach » thu sach, su sach, tu cach
te sach » toc sach
ky dang » ky nang, ky danh
xay hoi » xa hoi, tay hoi, cay phoi
hieu ve » hieu va, hieu van
ve cach » va cach, ve cac, ve canh
vat cau » dat cau, va cau, van cau

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 (te sach)) ky dang xay hoi. hieu ve cach cua ban trinh vat cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky dang xay hoi. hieu ve cach cua ban trinh vat cau tren.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (te sach)) ky dang xay hoi. hieu ve cach cua ban trinh vat cau tren*.