Perhaps you should try some spelling variations:
va thanh » ban thanh, va tinh, le thanh
te sach » toc sach
sach ky » sac ky, sach y, sach ty
ky mang » ky nang, ke mang, ky dang
may hoi » may thoi, tay hoi, mai hoi
hieu va » lieu va, hieu qua
cac tuc » cac toc, cac tu, cac tac
su viet » so viet
dam su » dan su, da su, dat su

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 ky mang may hoi. hieu va cac tuc ((va thanh) OR (gia thanh)) dam su viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky mang may hoi. hieu va cac tuc ((va thanh) OR (gia thanh)) dam su viet".
• Adding a wildcard symbol may retrieve word variants: te sach ky mang may hoi. hieu va cac tuc ((va thanh) OR (gia thanh)) dam su viet*.