Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
nang mai » nang ma, nang tai, lang mai
danh sai » dung sai, danh bat, danh dau
va triet » va thiet, va trien, ve triet
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, lai hoi
hieu he » hieu ve, hiem he, hieu le
ha danh » han danh, hoa danh, ha anh
he nam » ha nam, nghe nam

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

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