Perhaps you should try some spelling variations:
nang ma » tang ma, sang ma, nang cao
hieu he » hieu ve, hiem he, hieu le
doan vi » doan va, don vi, doan thi
cua tre » cua te, cuu tre, cua triet
tu sai » tu bai, tu san, tu cai
sai ky » sac ky
he nam » ha nam, nghe nam
nam tu » nam thu, nam thuc
dan vi » don vi, dan va, gan vi

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sai ky nang ma hoa. hieu he nam tu va ((dan vi) OR (doan vi)) cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sai ky nang ma hoa. hieu he nam tu va ((dan vi) OR (doan vi)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sai ky nang ma hoa. hieu he nam tu va ((dan vi) OR (doan vi)) cua tre*.