Perhaps you should try some spelling variations:
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
cac dai » cac dan, cac bai, can dai
van mat » van dat, van man, van mao
mat cua » ma cua, manh cua, mang cua
cua tre » cua te, cuu tre, cua triet
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
dai va » mai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky nang xa hoi. ((hieu va) or (lieu va)) cac dai va van mat cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky nang xa hoi. ((hieu va) OR (lieu va)) cac dai va van mat cua tre*.