Perhaps you should try some spelling variations:
nguoi sach » nguoi san, nuoc sach
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
cau luu » cau luc
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
va cau » van cau, va cac, va dau
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: nguoi sach ((ty nang) or (ty hang)) xa hoi. hieu va cau luu ((van hanh) OR (ban hanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: nguoi sach ((ty nang) OR (ty hang)) xa hoi. hieu va cau luu ((van hanh) OR (ban hanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "nguoi sach ((ty nang) or (ty hang)) xa hoi. hieu va cau luu ((van hanh) OR (ban hanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: nguoi sach ((ty nang) or (ty hang)) xa hoi. hieu va cau luu ((van hanh) OR (ban hanh)) vi cua tre*.