Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hieu van » hieu va, thien van, lieu va
thanh va » thanh van, hanh va, thanh ha
va thanh » gia thanh, ban thanh, va tinh
thai cua » than cua, tai cuc, tri cua
dang xay » dang van, van xay
hai cuc » tai cuc, hai cua, hai huoc
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
va cua » va chua, via cua, ca cua

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: te sach y ((nang ma) OR (dang xay)) hoi. hieu van ((hai cuc) OR (thai cua)) va thanh va cua triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang ma) or (dang xay)) hoi. hieu van ((hai cuc) OR (thai cua)) va thanh va cua triet~".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang ma) or (dang xay)) hoi. hieu van ((hai cuc) OR (thai cua)) va thanh va cua triet*.