Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
van hanh » van thanh, van anh, van ban
ban hanh » ban hang
su triet » su viet, su tien, ve triet
tu sach » thu sach, su sach, te sach
dang ma » dang mau, dang mam, dang mat
hieu va » lieu va, hieu qua
va nham » va cham, va tham, va nha
y dang » ky dang, 2 dang, _ dang
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 y dang ma hoi. hieu va nham thuc ((van hanh) or (ban hanh)) ki su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y dang ma hoi. hieu va nham thuc ((van hanh) OR (ban hanh)) ki su triet.
• Adding a wildcard symbol may retrieve word variants: tu sach y dang ma hoi. hieu va nham thuc ((van hanh) or (ban hanh)) ki su triet*.