Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
van nang » van quang, van ban, van dong
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
ve triet » va trien, su triet
te sach » toc sach
hieu va » lieu va, hieu qua
va cham » va chat, va tham
x hoi » xa hoi, o hoi, x ho
vi ve » va ve, gi ve, ve ve

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 (hoc sach)) van nang x hoi. hieu va cham soc ((van hanh) OR (ban hanh)) vi ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (hoc sach)) van nang x hoi. hieu va cham soc ((van hanh) OR (ban hanh)) vi ve triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (hoc sach)) van nang x hoi. hieu va cham soc ((van hanh) OR (ban hanh)) vi ve triet*".