Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
va hanh » va thanh, va danh, ban hanh
hieu va » lieu va, hieu qua
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cuu tre » cua tre, cau tren, cau treo
va nam » van nam, ha nam, va nay
nam tu » nam thu, nam thuc
di cuu » di cau, di cua, dinh cuu

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 ((ty nang) OR (ty hang)) xa hoi. hieu va nam tu ((va hanh) or (van hanh)) di cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty nang) OR (ty hang)) xa hoi. hieu va nam tu ((va hanh) OR (van hanh)) di cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty nang) OR (ty hang)) xa hoi. hieu va nam tu ((va hanh) or (van hanh)) di cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((ty nang) OR (ty hang)) xa hoi. hieu va nam tu ((va hanh) or (van hanh)) di cuu tre*.