Perhaps you should try some spelling variations:
dinh cuu » dinh chi
hieu van » hieu va, thien van, lieu va
van tham » van thanh, van tuan, van chat
te sach » toc sach
sach ky » sac ky, sach y, sach ty
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
doc va » duoc va, hoc va, duc va
vi cuu » vi luu, vinh cuu
soc va » hoc va, loc va, goc va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky tang xa hoi. hieu van tham ((soc va) OR (doc va)) hanh ((vi cuu) or (dinh cuu)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky tang xa hoi. hieu van tham ((soc va) OR (doc va)) hanh ((vi cuu) OR (dinh cuu)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky tang xa hoi. hieu van tham ((soc va) OR (doc va)) hanh ((vi cuu) or (dinh cuu)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach ky tang xa hoi. hieu van tham ((soc va) OR (doc va)) hanh ((vi cuu) or (dinh cuu)) tre*.