Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thanh di » thanh doi, thanh de, thanh do
cuu tre » cau tren, cau treo
cua tre » cua te, cua triet, dua tren
van hac » van hoc, van ha, van hai
van cac » van cau, van bac, dan cac
nang xa » nang x, lang xa, nang ma
can ky » van ky, dan ky, ban ky
toi va » thoi va, tuoi va, hoi va
tu can » tu ban, tu cac, thu canh

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu can ky nang xa hoi. hieu ((van cac) OR (van hac)) toi va thanh di ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu can ky nang xa hoi. hieu ((van cac) OR (van hac)) toi va thanh di ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu can ky nang xa hoi. hieu ((van cac) OR (van hac)) toi va thanh di ((cua tre) or (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: tu can ky nang xa hoi. hieu ((van cac) OR (van hac)) toi va thanh di ((cua tre) or (cuu tre))*.