Perhaps you should try some spelling variations:
manh tinh » man tinh, manh binh, canh tinh
cua viet » ca viet, hoa viet, cua vat
tinh hai » tinh thai, tinh chat, trinh han
cham duc » pham duc, pham duy, phan duc
hai cua » thai cua, dai cua, hoi cua
tu sach » thu sach, su sach, te sach
ty hang » ly hang, ty xang, thi hang
ty nang » ky nang, ty xang, ly nang
hieu ve » hieu va, hieu van
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((ty nang) or (ty hang)) x hoi. hieu ve ((cham duc) OR (cham soc)) manh tinh hai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ty nang) OR (ty hang)) x hoi. hieu ve ((cham duc) OR (cham soc)) manh tinh hai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ty nang) or (ty hang)) x hoi. hieu ve ((cham duc) OR (cham soc)) manh tinh hai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ty nang) or (ty hang)) x hoi. hieu ve ((cham duc) OR (cham soc)) manh tinh hai cua viet*.