Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
cac thuc » cach thuc, cac thu, can thuc
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
mai hoi » mai khoi, dai hoi, lai hoi
hieu va » lieu va, hieu qua
vai cua » dai cua, hai cua, lai cua
ma hoi » xa hoi, ma hoa, me hoi
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach thi nang ((ma hoi) or (mai hoi)). hieu va cac thuc van hanh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach thi nang ((ma hoi) OR (mai hoi)). hieu va cac thuc van hanh vai cua te.
• Adding a wildcard symbol may retrieve word variants: toc sach thi nang ((ma hoi) or (mai hoi)). hieu va cac thuc van hanh vai cua te*.