Perhaps you should try some spelling variations:
luan phan » luan van, luan hoan
hieu luan » hieu luat, hieu quan, tieu luan
phan duc » pham duc, phan tu, phan dau
van hanh » van thanh, ban hanh, van anh
tu sach » thu sach, su sach, te sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
duc van » duc va, duc tan, duc manh
vi su » va su, ki su, oi su
ve su » va su

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ty nang xa hoi. hieu luan phan duc van hanh ((vi su) OR (ve su)) viet~".
• Adding a wildcard symbol may retrieve word variants: tu sach ty nang xa hoi. hieu luan phan duc van hanh ((vi su) OR (ve su)) viet*.