Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
vien cac » vien bach, vien dai, vien da
thoi van » thoai van, thai van, tho van
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
thi van » thi lan, thi hanh, thi nang
hanh ve » hanh vi, hanh va, hanh kem
ve su » va su

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 ((thoi van) OR (thi van)) hanh ve su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang xa hoi. hieu vien cac ((thoi van) OR (thi van)) hanh ve su triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky nang xa hoi. hieu vien cac ((thoi van) OR (thi van)) hanh ve su triet*.