Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
toc sach » hoc sach, doc sach, thuoc sach
nang tai » hang tai, tang tai, sang tai
hieu van » hieu va, thien van, lieu va
ban nuoc » ban duoc, ban nuoi, ban thuoc
tai hoi » tai khoi, dai hoi, tai hai
va tinh » may tinh
co viet » so viet, o viet, hoc viet
y nang » ky nang, ly nang, v nang
va dan » ca dan, va dao, va dau
vi co » vi con, voi co, vi mo

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y nang tai hoi. hieu van ban nuoc ((va dan) or (((ban thanh) or (va tinh)))) vi co viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y nang tai hoi. hieu van ban nuoc ((va dan) OR (((ban thanh) OR (va tinh)))) vi co viet.
• Adding a wildcard symbol may retrieve word variants: toc sach y nang tai hoi. hieu van ban nuoc ((va dan) or (((ban thanh) or (va tinh)))) vi co viet*.