Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
van hanh » van thanh, ban hanh, van anh
vu sach » vu bach, su sach, vu khach
xuc van » duc van, luc van, vuc van
ca viet » va viet, co viet, hoa viet
nang o » nang co, nang ho, nang ro
ve cam » ve cham, ve cac, ve cai
va cam » va cham, va cac, va cao
o hoi » co hoi, o hoc, o hai
vi ca » vit ca, li ca, va ca

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach thi nang o hoi. hieu ((ve cam) or (va cam)) xuc van hanh vi ca viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach thi nang o hoi. hieu ((ve cam) OR (va cam)) xuc van hanh vi ca viet.
• Adding a wildcard symbol may retrieve word variants: vu sach thi nang o hoi. hieu ((ve cam) or (va cam)) xuc van hanh vi ca viet*.