Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
nganh ky » nganh y, nganh xay, hanh ky
sanh ky » hanh ky, sang ky, thanh ky
va hanh » van hanh, va danh, ban hanh
cac dac » cac dan, cac dai, cac bac
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
tang xa » trang xa, tang ma, lang xa
vi cua » vai cua, di cua
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: so ((sanh ky) or (nganh ky)) tang xa hoi. hieu ve cac dac ((va hanh) OR (va thanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sanh ky) OR (nganh ky)) tang xa hoi. hieu ve cac dac ((va hanh) OR (va thanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sanh ky) or (nganh ky)) tang xa hoi. hieu ve cac dac ((va hanh) OR (va thanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: so ((sanh ky) or (nganh ky)) tang xa hoi. hieu ve cac dac ((va hanh) OR (va thanh)) vi cua tre*.