Perhaps you should try some spelling variations:
hanh trinh » canh tranh, hanh chinh
luan trong » quan trong, luat trong, luan tuong
cong thanh » dong thanh, cong trinh, truong thanh
lieu tinh » trieu tinh, diep tinh, bien tinh
anh tang » anh bang, anh dang, anh nang
cong tan » cong tac, cong san, cong ty
toan cao » toan ban, toan tap
so lieu » so dieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: so lieu tinh - ((hanh trinh) or (anh tang)) luan trong ((cong tan) OR (cong thanh)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so lieu tinh - ((hanh trinh) OR (anh tang)) luan trong ((cong tan) OR (cong thanh)) toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so lieu tinh - ((hanh trinh) or (anh tang)) luan trong ((cong tan) OR (cong thanh)) toan cao*".