Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
viec hoc » viec doc, viec khoa, viec nhom
va triet » va thiet, va trien, ve triet
ty nang » ky nang, ty xang, ty hang
su sach » so sach, vu sach
tu sach » thu sach, te sach, tu cach
x hoi » xa hoi, o hoi, x ho
vi va » vi van, vai va, vu va

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) or (su sach)) ty nang x hoi. hieu viec hoc (nuoc OR duoc) va thanh vi va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ty nang x hoi. hieu viec hoc (nuoc OR duoc) va thanh vi va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ty nang x hoi. hieu viec hoc (nuoc OR duoc) va thanh vi va triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) ty nang x hoi. hieu viec hoc (nuoc OR duoc) va thanh vi va triet*.