Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
cham tuc » nham thuc, pham thuc, tham thuc
hanh tai » thanh tai, hang tai, han tai
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
sai ky » sac ky
tuc va » thuc va, truc va, tuc xa
tai va » thai va, mai va, tri va
x hoi » xa hoi, o hoi, x ho
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sai ky)) nang x hoi. hieu van cham tuc va hanh tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sai ky)) nang x hoi. hieu van cham tuc va hanh tai va thiet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sai ky)) nang x hoi. hieu van cham tuc va hanh tai va thiet*.