Perhaps you should try some spelling variations:
hieu vien » hieu hien, hieu viec, thieu nien
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
vat hanh » vat thanh, va hanh, nhat hanh
bac hoc » bai hoc, bac ho
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
cac hoc » cach hoc, cac hop, cac toc
nang xa » nang x, lang xa, nang ma
ty nang » ky nang, ty xang, ty hang
vi su » va su, ve su, ki 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 ty nang xa hoi. hieu vien ((cac hoc) OR (bac hoc)) ((vat hanh) OR (van hanh)) vi su triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ty nang xa hoi. hieu vien ((cac hoc) OR (bac hoc)) ((vat hanh) OR (van hanh)) vi su triet".
• Adding a wildcard symbol may retrieve word variants: su sach ty nang xa hoi. hieu vien ((cac hoc) OR (bac hoc)) ((vat hanh) OR (van hanh)) vi su triet*.