Perhaps you should try some spelling variations:
cau triet » cau trieu, su triet, cua triet
danh vai » danh sai, danh va, doanh van
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach ty, sach kem
cua tre » cua te, cuu tre, cua triet
ta danh » tac danh, tao danh, tap danh
van cac » van hac, van cau, van bac
nang xa » nang x, lang xa, nang ma
cac toi » cac thoi
toi ta » toi tap, toi la, toi da

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) OR (sach y)) nang xa hoi. hieu van cac toi ta danh vai ((cua tre) or (cau triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ky) OR (sach y)) nang xa hoi. hieu van cac toi ta danh vai ((cua tre) OR (cau triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ky) OR (sach y)) nang xa hoi. hieu van cac toi ta danh vai ((cua tre) or (cau triet))".
• Adding a wildcard symbol may retrieve word variants: te ((sach ky) OR (sach y)) nang xa hoi. hieu van cac toi ta danh vai ((cua tre) or (cau triet))*.