Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu vien » hieu hien, hieu viec, thieu nien
va thanh » gia thanh, ban thanh, va tinh
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
vien cac » vien bach, vien dai, vien da
vu khanh » vu thanh, van khanh, duy khanh
nang ma » tang ma, sang ma, nang cao
va hanh » van hanh, va danh, ban hanh
te sach » toc sach
ma hoi » mai hoi, xa hoi, ma hoa
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (vu khanh)) ky nang ma hoi. hieu vien cac nuoc ((va hanh) OR (va thanh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (vu khanh)) ky nang ma hoi. hieu vien cac nuoc ((va hanh) OR (va thanh)) vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (vu khanh)) ky nang ma hoi. hieu vien cac nuoc ((va hanh) OR (va thanh)) vi cua triet".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (vu khanh)) ky nang ma hoi. hieu vien cac nuoc ((va hanh) OR (va thanh)) vi cua triet*.