Perhaps you should try some spelling variations:
truc van » truc va, thuc van, truc ban
bach van » bach dan, cach van, bach dang
van hanh » van thanh, ban hanh, van anh
sach van » sach han, sach va, cach van
cua tre » cuu tre, cua triet, dua tren
hanh de » hanh ve, hanh kem
hieu ve » hieu va, hieu van
ve cau » ke cau, va cau, ve cac
nang o » nang co, nang ho, nang ro
cua te » cua tu
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 van) OR (bach van)) nang o hoi. hieu ve cau truc van hanh de ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach van) OR (bach van)) nang o hoi. hieu ve cau truc van hanh de ((cua tre) OR (cua te))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach van) OR (bach van)) nang o hoi. hieu ve cau truc van hanh de ((cua tre) or (cua te))*".