Perhaps you should try some spelling variations:
cac thuc » cach thuc, cac thu, can thuc
vat hanh » vat thanh, van hanh, va hanh
dau treo » dau tren, cau treo, dau theo
su sach » so sach, vu sach
qua cac » cua cac
hanh va » hang va, hanh vi
y nang » ky nang, ly nang, v nang
va dau » va dao
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach y nang ((5 hoi) or (o hoi)). hieu qua cac thuc vat hanh va dau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((5 hoi) OR (o hoi)). hieu qua cac thuc vat hanh va dau treo.
• Adding a wildcard symbol may retrieve word variants: su sach y nang ((5 hoi) or (o hoi)). hieu qua cac thuc vat hanh va dau treo*.