Perhaps you should try some spelling variations:
thi cong » tai cong, thien cong
cong tac » cong ty
hieu van » hieu va, thien van, lieu va
lam duoc » nam duoc, luat duoc, lam thuoc
va triet » va thiet, va trien, ve triet
sac thi » sac thai, sat thi, cac thi
tac hoi » tao hoi, tay hoi, tac hai
van lam » van nam
duoc va » nuoc va, duc va, duoc ma
anh tai » hanh tai, anh thai, vanh tai
te sac » te sach, te cac, te san
anh va » hanh va

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac thi cong tac hoi. hieu van lam duoc va ((anh tai) or (anh va)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac thi cong tac hoi. hieu van lam duoc va ((anh tai) OR (anh va)) va triet.
• Adding a wildcard symbol may retrieve word variants: te sac thi cong tac hoi. hieu van lam duoc va ((anh tai) or (anh va)) va triet*.