Perhaps you should try some spelling variations:
hieu viec » nhieu viec, hieu ve, sieu viet
va trien » va truyen, va thiet, va tuyen
va triet » va thiet, ve triet, cua triet
thanh vi » hanh vi, thanh va, thanh ve
va thanh » gia thanh, ban thanh, va tinh
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
viec cac » vien cac, viec cua, viec lam
su sach » so sach, vu sach
tu sach » thu sach, te sach, tu cach
x hoi » xa hoi, o hoi, x ho

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