Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cam thuc » am thuc, cam thu, can thuc
nam thuc » nam thuoc, am thuc, nam thu
hieu ve » hieu va, hieu van
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hanh di » hanh vi, hanh de, danh di
hang di » hang doi, hang vi, hang dien
su sach » so sach, vu sach

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 ky nang xa hoi. hieu ve ((cam thuc) OR (nam thuc)) van ((hanh di) or (hang di)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang xa hoi. hieu ve ((cam thuc) OR (nam thuc)) van ((hanh di) OR (hang di)) cua triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang xa hoi. hieu ve ((cam thuc) OR (nam thuc)) van ((hanh di) or (hang di)) cua triet*".