Perhaps you should try some spelling variations:
hanh vai » hanh vi, hanh va, hanh tai
ban hanh » ban hang
te sach » toc sach
sach ky » sac ky, sach y, sach ty
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
hieu ve » hieu va, hieu van
ve cac » va cac, vien cac
lo ban » co ban, lo van, ly ban
ma hoi » mai hoi, xa hoi, me hoi
cac lo » cac lop, cac co, cac bo

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 nang ((ma hoi) or (ma hoa)). hieu ve cac lo ban hanh vai ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((ma hoi) OR (ma hoa)). hieu ve cac lo ban hanh vai ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((ma hoi) or (ma hoa)). hieu ve cac lo ban hanh vai ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: te sach ky nang ((ma hoi) or (ma hoa)). hieu ve cac lo ban hanh vai ((cua tre) OR (cuu tre))*.