Perhaps you should try some spelling variations:
thanh luc » thanh luu, than luc, nhan luc
hanh tai » thanh tai, hang tai, han tai
hieu van » thien van, lieu va, hieu ve
su sach » so sach, vu sach
tai cua » thai cua, tai cuc, tri cua
va hanh » van hanh, va thanh, va danh
vu nang » vuc nang, va nang, vu dang
hieu va » lieu va, hieu qua
luc va » duc va, tuc va, loc va
v nang » va nang, van nang, voi nang
cua te » cua tu

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 ((v nang) OR (vu nang)) xa hoi. ((hieu van) or (hieu va)) thanh luc va hanh tai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((v nang) OR (vu nang)) xa hoi. ((hieu van) OR (hieu va)) thanh luc va hanh tai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((v nang) OR (vu nang)) xa hoi. ((hieu van) or (hieu va)) thanh luc va hanh tai cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((v nang) OR (vu nang)) xa hoi. ((hieu van) or (hieu va)) thanh luc va hanh tai cua te*.