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