Perhaps you should try some spelling variations:
cham thuc » nham thuc, pham thuc, tham thuc
thanh tay » thanh tai, thanh toan, thanh thuy
day nhanh » day thanh, duy nhanh, dac nhan
day hanh » day thanh, dao hanh, day manh
vu thanh » su thanh, vu khanh, cuu thanh
tay nang » tay nung, may nang, day nang
hieu ve » hieu va, hieu van
ve cham » va cham, ve chat, vu cham
cua tre » cua te, cuu tre, cua triet
te cua » tue cua, le cua, de cua
x hoi » o hoi, x ho, 5 hoi

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: vu thanh tay nang ((x hoi) OR (xa hoi)). hieu ve cham thuc ((day hanh) or (day nhanh)) te cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu thanh tay nang ((x hoi) OR (xa hoi)). hieu ve cham thuc ((day hanh) OR (day nhanh)) te cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu thanh tay nang ((x hoi) OR (xa hoi)). hieu ve cham thuc ((day hanh) or (day nhanh)) te cua tre*".