Perhaps you should try some spelling variations:
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
cam tuc » cam xuc, nam thuc, dam thuc
va hanh » van hanh, va thanh, va danh
cu tren » tu tren, dua tren
tu dan » tuc dan, tu ban, cu dan
dan ky » van ky
cam tu » cam thu, nam tu, dam tu
kem cu » kem chu, kem cd

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu dan ky ((nang xa) or (nang x)) hoi. hieu ve ((cam tuc) OR (cam tu)) va hanh kem cu tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu dan ky ((nang xa) OR (nang x)) hoi. hieu ve ((cam tuc) OR (cam tu)) va hanh kem cu tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu dan ky ((nang xa) or (nang x)) hoi. hieu ve ((cam tuc) OR (cam tu)) va hanh kem cu tren".
• Adding a wildcard symbol may retrieve word variants: tu dan ky ((nang xa) or (nang x)) hoi. hieu ve ((cam tuc) OR (cam tu)) va hanh kem cu tren*.