Perhaps you should try some spelling variations:
nang mai » nang ma, nang tai, lang mai
van hanh » van thanh, ban hanh, van anh
su sach » so sach, vu sach
va cham » va chat, va tham
hanh ki » hanh vi, hanh ky, hanh kien
xuc van » duc van, luc van, vuc van
su viet » so viet
sach vu » sach va, sach tu, sach uu
mai hoi » mai khoi, dai hoi, lai hoi
vu nang » vuc nang, va nang, vu dang
va cam » va cac, va cao, va cai
ki su » ky su

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach vu nang mai hoi. hieu ((va cam) OR (va cham)) xuc van hanh ki su viet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach vu nang mai hoi. hieu ((va cam) OR (va cham)) xuc van hanh ki su viet".
• Adding a wildcard symbol may retrieve word variants: su sach vu nang mai hoi. hieu ((va cam) OR (va cham)) xuc van hanh ki su viet*.