Perhaps you should try some spelling variations:
trinh luan » trinh luat, trinh quan, trinh toan
lang thang » cang thang, dang thanh, hung thang
trinh han » trinh quan
dang cong » dung cong
cong lang » cong vang, cong luong, cong quang
thi hanh » thi thanh
thang va » hang va, trang va, thong va
doi thi » doi thoi, do thi, 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 thi hanh - canh ((trinh luan) or (trinh han)) dang cong lang thang va~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi thi hanh - canh ((trinh luan) OR (trinh han)) dang cong lang thang va*.