Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
thuc van » thuc vat, thuc dan, thuc va
cac thuc » cach thuc, cac thu, can thuc
hang vi » hang va, hanh vi, khang voi
hang di » hang doi, hang dien, hang dich
co sach » bo sach, cuon sach, hoc sach
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
ve cac » va cac, vien cac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: co sach y ((nang xa) OR (nang ma)) hoi. hieu ve cac thuc van ((hang di) or (hang vi)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: co sach y ((nang xa) OR (nang ma)) hoi. hieu ve cac thuc van ((hang di) OR (hang vi)) su triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "co sach y ((nang xa) OR (nang ma)) hoi. hieu ve cac thuc van ((hang di) or (hang vi)) su triet*".