Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
ban thanh » ban hanh, ban hang
su triet » su viet, su tien, ve triet
van hanh » van thanh, ban hanh, van anh
sach tu » sach thu, cach tu, sach ty
hieu va » lieu va
dang ma » dang mau, dang mam, dang mat
tu dang » thu dang, tu dong, su 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 tu dang ma hoi. ((hieu va) or (hieu qua)) nham thuc ((van hanh) or (ban thanh)) ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu dang ma hoi. ((hieu va) OR (hieu qua)) nham thuc ((van hanh) OR (ban thanh)) ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach tu dang ma hoi. ((hieu va) or (hieu qua)) nham thuc ((van hanh) or (ban thanh)) ki su triet*.