Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
hanh tai » thanh tai, hang tai, han tai
su triet » su viet, su tien, ve triet
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
ve bac » ve bao, ve cac, ve ban
bo van » vo van, so van, do van
tai su » tai so, tai tu, lai su
x hoi » o hoi, x ho, 5 hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sach ky nang ((x hoi) or (xa hoi)). hieu ve bac bo van hanh tai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky nang ((x hoi) OR (xa hoi)). hieu ve bac bo van hanh tai su triet.
• Adding a wildcard symbol may retrieve word variants: vu sach ky nang ((x hoi) or (xa hoi)). hieu ve bac bo van hanh tai su triet*.