Perhaps you should try some spelling variations:
tham thuc » pham thuc, tam thuc, thai thuc
nham thuc » nhan thuc, nam thuc, nham thu
su triet » su viet, su tien, ve triet
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
ky dang » ky nang, ky danh
xay hoi » tay hoi, cay phoi, gay thoi
va hanh » van hanh, va thanh, va danh
vi su » va su, ve su, ki su

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

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