Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dung sai » dung tai, dung va, dung dat
nam dung » nam vung, nam dong, am dung
cua tre » cua te, cuu tre, dua tren
sach ty » sach y, sach tu, sach thu
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
ty nang » ky nang, ty xang, ty hang
hieu he » hieu ve, hiem he, hieu le
he nam » ha nam, nghe nam
nam tu » nam thu, nam thuc
tu nam » su nam
ma hoi » xa hoi, ma hoa, me hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty nang ((ma hoi) or (mai hoi)). hieu he nam tu nam dung sai ((cua tre) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty nang ((ma hoi) OR (mai hoi)). hieu he nam tu nam dung sai ((cua tre) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: su sach ty nang ((ma hoi) or (mai hoi)). hieu he nam tu nam dung sai ((cua tre) or (cua triet))*.