Perhaps you should try some spelling variations:
ban hanh » ban hang
tuan duc » tran duc, xuan duc, than duc
van tuan » van quan, van ban, anh tuan
hieu van » hieu va, thien van, lieu va
sach thu » sach thue, sach thieu, sach tham
sach ty » sach y, sach tu, xach tay
duc ban » duc tan, duc van, dua ban
hai cua » thai cua, hoi cua, lai cua
xang x » nang x
x hoi » xa hoi, o hoi, x ho

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) OR (sach thu)) xang x hoi. hieu van tuan duc ban hanh ((hai cua) or (dai cua)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) xang x hoi. hieu van tuan duc ban hanh ((hai cua) OR (dai cua)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) OR (sach thu)) xang x hoi. hieu van tuan duc ban hanh ((hai cua) or (dai cua)) triet*".