Perhaps you should try some spelling variations:
te sach » toc sach
hanh di » hanh de, hang di, danh di
tuc van » thuc van, truc van, tuc va
cac tuc » cac toc, cac tu, cac tac
hieu va » lieu va, hieu qua
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cua tre » cua te, cuu tre, cua triet

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 cac tuc van ((hanh di) or (hanh vi)) cua 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 cac tuc van ((hanh di) OR (hanh vi)) cua 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 cac tuc van ((hanh di) or (hanh vi)) cua tre*".