Perhaps you should try some spelling variations:
trinh chat » tinh chat, trinh luat, trinh han
trinh bay » trinh may, trinh ban, trinh bao
trinh cac » trinh cau, trinh chao, trinh cham
cac tap » cac cap, cac tac, cac tai
cot soi » cot loi, cong soi
dan va » doan va, ban va, han va
co soi » co so, co hoi, co loi

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

• If you are trying to use Boolean operators, they must be ALL CAPS: chuong ((trinh bay) OR (((trinh cac) OR (trinh chat)))) ((dan va) OR (dan ca)) cac tap ((co soi) OR (cot soi)) viet nam~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "chuong ((trinh bay) or (((trinh cac) OR (trinh chat)))) ((dan va) or (dan ca)) cac tap ((co soi) or (cot soi)) viet nam~".
• Adding a wildcard symbol may retrieve word variants: chuong ((trinh bay) or (((trinh cac) OR (trinh chat)))) ((dan va) or (dan ca)) cac tap ((co soi) or (cot soi)) viet nam*.