Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
cam thuc » am thuc, nam thuc, cam thu
va danh » va dinh, va dan, dia danh
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
va hanh » van hanh, va thanh, ban hanh
tu sac » tu cac, tu san, tu bac
ve cam » ve cham, ve cac, va cam

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

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