Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
dung doi » huong doi, dung tai, dung co
vat dung » van dung, va dung, viet dung
sach ty » sach tu, sach thu, xach tay
cac toc » cac toi, cac nuoc, cac thoi
cac tuc » cac tu, cac tac, cac nuoc
doi su » oi su, don su, voi su
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) or (cac toc)) vat dung doi su 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) OR (cac toc)) vat dung doi su triet.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach y)) nang x hoi. hieu qua ((cac tuc) or (cac toc)) vat dung doi su triet*.