Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
thanh tai » thanh toan, doanh tai, thanh san
cua tre » cua te, cuu tre, cua triet
ve pham » vi pham, v pham, ve phan
hieu ve » hieu va, hieu van
ky tang » ky nang, ky dang, kho tang
sac ky » cac ky, sai ky
ma hoi » mai hoi, ma hoa, me hoi
su sac » su sach, su cac, su xac

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky tang ((ma hoi) OR (xa hoi)). hieu ve pham duc tan ((thanh tai) or (thanh hai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky tang ((ma hoi) OR (xa hoi)). hieu ve pham duc tan ((thanh tai) OR (thanh hai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sac ky tang ((ma hoi) OR (xa hoi)). hieu ve pham duc tan ((thanh tai) or (thanh hai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sac ky tang ((ma hoi) OR (xa hoi)). hieu ve pham duc tan ((thanh tai) or (thanh hai)) cua tre*.