Perhaps you should try some spelling variations:
danh sai » dung sai, danh bat, danh dau
xac danh » xac dinh, tac danh, sach danh
cua tre » cuu tre, cua triet, dua tren
thu xac » thau xay
hieu he » hieu ve, hiem he, hieu le
sach ky » sac ky, sach y, sach kem
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach tu, sach thu
he nam » ha nam, nghe nam
cua te » cua tu

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) or (sach ty)) nang ma hoa. hieu he nam thu xac danh sai ((cua tre) OR (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach ty)) nang ma hoa. hieu he nam thu xac danh sai ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sach ty)) nang ma hoa. hieu he nam thu xac danh sai ((cua tre) OR (cua te))".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sach ty)) nang ma hoa. hieu he nam thu xac danh sai ((cua tre) OR (cua te))*.