Perhaps you should try some spelling variations:
pham thuc » phap thuc, pham chuc, nham thuc
hoc sach » hoc cac, hoc anh
thuc van » thuc vat, thuc dan, thuc va
van hanh » van thanh, ban hanh, van anh
hanh vai » hanh vi, hanh va, hanh tai
su triet » su viet, su tien, ve triet
ky sang » ky nang, ky dang, ky tang
sang ma » tang ma, nang ma, sang tao
hieu vi » hieu voi, hieu va, hieu ve
ma hoi » mai hoi, xa hoi, ma hoa
vai su » va su, van su, lai su

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((hoc sach) or (hoc sinh)) ky sang ma hoi. hieu vi pham thuc van hanh vai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc sach) OR (hoc sinh)) ky sang ma hoi. hieu vi pham thuc van hanh vai su triet.
• Adding a wildcard symbol may retrieve word variants: ((hoc sach) or (hoc sinh)) ky sang ma hoi. hieu vi pham thuc van hanh vai su triet*.