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
tan hanh » tan thanh, tang hanh, toan hanh
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

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 tan hanh ((va su) OR (ve su)) viet~.
• Adding a wildcard symbol may retrieve word variants: tu sach ty lang xa hoi. hieu luan phan duc tan hanh ((va su) or (ve su)) viet*.