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
va hanh » van hanh, va thanh, ban hanh
su sach » so sach, vu sach
hieu ve » hieu va, hieu van
nang xa » lang xa, nang ma, mang xa
sach v » sach va, sach y, sach 2
ve cam » ve cham, ve cac, va cam
vi su » va su, ve su, ki su

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