Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
van thanh » ban thanh, van tuan
su triet » su viet, su tien, ve triet
van hanh » ban hanh, van anh, van ban
sach vu » sach va, sach tu, sach uu
hieu va » lieu va
dang ma » dang mau, dang mam, dang mat
vu dang » su dang, vu quang, cua dang
tu sach » thu sach, su sach, te sach
ma hoi » mai hoi, xa hoi, ma hoa
ki su » ky su

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