Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
thuc van » thuc vat, thuc dan, thuc va
su triet » su tien, ve triet
van hanh » van thanh, ban hanh, van anh
hanh ki » hanh vi, hanh ky, hanh kien
tu sach » thu sach, su sach, te sach
sach vu » sach va, sach tu, sach uu
va tham » van tham, va cham, va thanh
hieu va » lieu va, hieu qua
dang ma » dang mau, dang mam, dang mat
vu dang » su dang, vu quang, cua dang
su viet » so viet
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach vu dang ma hoi. hieu va tham thuc van hanh ki ((su triet) OR (su viet))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach vu dang ma hoi. hieu va tham thuc van hanh ki ((su triet) OR (su viet))".
• Adding a wildcard symbol may retrieve word variants: tu sach vu dang ma hoi. hieu va tham thuc van hanh ki ((su triet) OR (su viet))*.