Perhaps you should try some spelling variations:
trinh vat » trinh van, trinh luat, sinh vat
tong cong » trong cong, cong cong, dung cong
chi sach » chinh sach, chieu sach, co sach
tranh va » tranh van, trang va, thanh va
trinh va » trinh van, trinh ve, trinh vi
cong tan » cong tac, cong san, cong thanh
tan phan » toan phan, than phan, van phan
phan dau » phan tu, hang dau
doi chi » doi khi

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

• Performing a fuzzy search may retrieve terms with similar spellings: doi chi sach - canh ((tranh va) or (((trinh va) or (trinh vat)))) tong cong tan phan dau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi chi sach - canh ((tranh va) OR (((trinh va) OR (trinh vat)))) tong cong tan phan dau.
• Adding a wildcard symbol may retrieve word variants: doi chi sach - canh ((tranh va) or (((trinh va) or (trinh vat)))) tong cong tan phan dau*.