Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
cam thuc » am thuc, cam thu, can thuc
nam thuc » nam thuoc, am thuc, nam thu
hanh ve » hanh va, hanh kem
su sach » so sach, vu sach
sach da » sach dao, sach dat, sach dau
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
da nang » cam nang, kha nang, cao nang

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 da nang xa hoi. hieu ve ((cam thuc) or (nam thuc)) va ((hanh ve) OR (hanh vi)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach da nang xa hoi. hieu ve ((cam thuc) OR (nam thuc)) va ((hanh ve) OR (hanh vi)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach da nang xa hoi. hieu ve ((cam thuc) or (nam thuc)) va ((hanh ve) OR (hanh vi)) su triet".
• Adding a wildcard symbol may retrieve word variants: su sach da nang xa hoi. hieu ve ((cam thuc) or (nam thuc)) va ((hanh ve) OR (hanh vi)) su triet*.