Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
nam tuc » nam thuc, nam truc, nam tu
xa hanh » xa thanh, xa khanh, va hanh
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
y nang » ky nang, ly nang, v nang

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (su sach)) y nang xa hoi. hieu van nam tuc xa hanh vai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang xa hoi. hieu van nam tuc xa hanh vai ((cua tre) OR (cuu tre))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) y nang xa hoi. hieu van nam tuc xa hanh vai ((cua tre) OR (cuu tre))*".