Perhaps you should try some spelling variations:
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
hieu ve » hieu va, hieu van
ve pham » vi pham, v pham, ve phan
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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 ky ((nang x) or (((nang ma) OR (sang ma)))) hoi. hieu ve pham duc va danh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang x) OR (((nang ma) OR (sang ma)))) hoi. hieu ve pham duc va danh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang x) or (((nang ma) OR (sang ma)))) hoi. hieu ve pham duc va danh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang x) or (((nang ma) OR (sang ma)))) hoi. hieu ve pham duc va danh vi cua tre*.