Perhaps you should try some spelling variations:
doanh ca » doanh cua, doanh cao, doanh va
tu sach » thu sach, su sach, te sach
ve cham » va cham, ve chat, vu cham
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
lo van » le van, vo van, so van
ca cua » co cua
lo va » lao va, ly va, le va

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 ((ky nang) or (ty xang)) xa hoi. hieu ve cham ((lo va) OR (lo van)) doanh ca cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky nang) OR (ty xang)) xa hoi. hieu ve cham ((lo va) OR (lo van)) doanh ca cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky nang) or (ty xang)) xa hoi. hieu ve cham ((lo va) OR (lo van)) doanh ca cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky nang) or (ty xang)) xa hoi. hieu ve cham ((lo va) OR (lo van)) doanh ca cua tre*.