Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
sach ky » sach y, sach ty, sach kem
hieu ve » hieu va, hieu van
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
cac vo » cac co, cac vi, cac bo
anh vi » anh va, anh ve, anh vu
x hoi » xa hoi, o hoi, x ho

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 (sac ky)) nang x hoi. hieu ve cac vo van ((anh vi) OR (hanh vi)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. hieu ve cac vo van ((anh vi) OR (hanh vi)) cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang x hoi. hieu ve cac vo van ((anh vi) OR (hanh vi)) cua triet*".