Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
hanh vai » hanh vi, hanh va, hanh tai
thi hang » thi nang, thi hong, thi thanh
nam thuc » nam thuoc, am thuc, nam thu
thi hanh » thi thanh
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
hieu va » lieu va, hieu qua
tu sach » thu sach, su sach, te sach
vu sach » vu bach, su sach, vu khach
va nam » van nam, ha nam, va nay
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: ((tu sach) or (vu sach)) ((thi hang) or (thi hanh)) xa hoi. hieu va nam thuc va hanh vai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) ((thi hang) OR (thi hanh)) xa hoi. hieu va nam thuc va hanh vai su triet.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) ((thi hang) or (thi hanh)) xa hoi. hieu va nam thuc va hanh vai su triet*.