Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh va » thanh van, hanh va, thanh ha
toc sach » hoc sach, doc sach, thuoc sach
tham soc » cham soc, tham nuoc, thai son
hieu van » hieu va, thien van, lieu va
soc ban » hoc ban, coc ban, so ban
ca tren » cau tren, cu tren, la tren
thi van » thi lan, thi hanh, thi nang
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
va ca » va cac, va cao, va cai

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) OR (toc sach)) ky lang xa hoi. ((hieu van) or (thi van)) tham soc ban thanh va ca tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky lang xa hoi. ((hieu van) OR (thi van)) tham soc ban thanh va ca tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky lang xa hoi. ((hieu van) or (thi van)) tham soc ban thanh va ca tren".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ky lang xa hoi. ((hieu van) or (thi van)) tham soc ban thanh va ca tren*.