Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dung sai » dung tai, dung va, dung dat
danh sai » danh bat, danh dau, hanh san
nam thuc » nam thuoc, am thuc, nam thu
hieu he » hieu ve, hiem he, hieu le
sach ky » sac ky, sach y, sach ty
thuc xa » thuc xay, tuc xa, thuc va
nang ma » tang ma, sang ma, mang may
tu sach » thu sach, su sach, te sach
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 ma) OR (nang cao)) hoa. hieu he nam thuc xa ((danh sai) or (dung sai)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang ma) OR (nang cao)) hoa. hieu he nam thuc xa ((danh sai) OR (dung sai)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang ma) OR (nang cao)) hoa. hieu he nam thuc xa ((danh sai) or (dung sai)) cua triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang ma) OR (nang cao)) hoa. hieu he nam thuc xa ((danh sai) or (dung sai)) cua triet*.