Perhaps you should try some spelling variations:
chat hoc » chat hoa, chat thom, cho hoc
van hanh » van thanh, ban hanh, van anh
hanh hai » thanh hai, nhanh hai, hang hai
hau treo » cau treo, cau theo, dau tren
su sach » so sach, vu sach
thi van » thi lan, thi hanh, thi nang
dao xuc » dao duc, dao tuc, dao xu
xuc van » duc van, luc van, vuc van
hai hau » hai chau, dai hau, hai hai
y nang » ky nang, ly nang, v nang

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 ((cau hoi) or (chat hoc)). ((thien van) OR (thi van)) dao xuc van hanh hai hau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach y nang ((cau hoi) OR (chat hoc)). ((thien van) OR (thi van)) dao xuc van hanh hai hau treo*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach y nang ((cau hoi) or (chat hoc)). ((thien van) OR (thi van)) dao xuc van hanh hai hau treo*".