Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
van hanh » van thanh, ban hanh, van anh
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
va danh » va dinh, va dan, va hanh
de su » den su, ve su, de 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 ky nang xa hoi. hieu vien cac nuoc ((van hanh) or (va danh)) de su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu vien cac nuoc ((van hanh) OR (va danh)) de su triet.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu vien cac nuoc ((van hanh) or (va danh)) de su triet*.