Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dung doi » huong doi, dung co, dung mo
sach ty » sach tu, sach thu, xach tay
qua cac » cua cac
cac tuc » cac toc, cac tu, cac tac
tuc vat » thuc vat, tuc va, tuc hat
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: su ((sach ty) or (sach y)) nang x hoi. hieu qua cac tuc vat ((dung doi) OR (dung tai)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach y)) nang x hoi. hieu qua cac tuc vat ((dung doi) OR (dung tai)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach ty) or (sach y)) nang x hoi. hieu qua cac tuc vat ((dung doi) OR (dung tai)) cua triet".
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach y)) nang x hoi. hieu qua cac tuc vat ((dung doi) OR (dung tai)) cua triet*.