Perhaps you should try some spelling variations:
thanh thai » thanh tai, nhanh thai, thanh thao
thanh hai » thanh phan, thanh hoa, thanh san
duc minh » duc anh
cua tre » cua te, cuu tre, cua triet
tang xa » trang xa, tang ma, lang xa
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
sac ky » cac ky
ve cac » va cac, vien cac

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