Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thanh vi » hanh vi, thanh va, thanh ve
xa thanh » va thanh, ha thanh, ta thanh
sach ky » sach y, sach ty, sach kem
cac tuc » cac toc, cac tu, cac tac
hieu ve » hieu va, hieu van
ve cac » va cac, vien cac
sac ky » cac ky, sai ky
so hoc » co hoc, mo hoc, so hoa
o hoc » co hoc, mo hoc, y hoc
vi su » va su, ve su, ki su

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 ((o hoc) or (so hoc)). hieu ve cac tuc xa thanh vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang ((o hoc) OR (so hoc)). hieu ve cac tuc xa thanh vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) nang ((o hoc) or (so hoc)). hieu ve cac tuc xa thanh vi su triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sac ky)) nang ((o hoc) or (so hoc)). hieu ve cac tuc xa thanh vi su triet*.