Perhaps you should try some spelling variations:
toc sach » doc sach, thuoc sach, nuoc sach
van hanh » van thanh, ban hanh, van anh
hoc sach » hoc sinh, hoc cac, hoc anh
chat xuc » chat huu, cam xuc, chao xu
xuc van » duc van, luc van, vuc van
va chat » van chat, va phat, cao chat
hieu va » lieu va, hieu qua
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
vi cua » vai cua, di cua
cua cu » cua chu, cua cau, cua su

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