Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
hanh di » hanh vi, hanh de, hang di
va hanh » van hanh, va thanh, va danh
hieu va » lieu va
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
cau tre » cau tren, cau treo, cau tra
cam tu » cam thu, nam tu, dam tu
di cau » da cau, diem cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((ty nang) or (ty hang)) xa hoi. ((hieu va) or (hieu qua)) cam tu va hanh di cau tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((ty nang) OR (ty hang)) xa hoi. ((hieu va) OR (hieu qua)) cam tu va hanh di cau tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ((ty nang) or (ty hang)) xa hoi. ((hieu va) or (hieu qua)) cam tu va hanh di cau tre*.