Perhaps you should try some spelling variations:
cau theo » cau thi, cau tao
tru nang » tra nang, tri nang, truc nano
van hanh » van thanh, ban hanh, van anh
van cam » van nam, van cau, van dam
van lam » van nam
luc van » luoc van, luu van, duc van
tu nong » tu dong, tu cong, tu tong
te sach » toc sach
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((tu nong) or (tru nang)) xa hoi. hieu ((van cam) or (van lam)) luc van hanh vi cau theo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nong) OR (tru nang)) xa hoi. hieu ((van cam) OR (van lam)) luc van hanh vi cau theo.
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nong) or (tru nang)) xa hoi. hieu ((van cam) or (van lam)) luc van hanh vi cau theo*.