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 lang » tay lang, ty xang, ty hang
lang xa » lang ha, dang xay, lang van
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.

• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty lang 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 lang xa hoi. hieu luan phan duc van hanh ((vi su) or (ve su)) viet*.