Perhaps you should try some spelling variations:
thong dung » thong cong, thong thuong
hanh trinh » canh tranh, hanh chinh
hieu lang » chieu sang, hieu quang, nhieu tang
trinh vat » trinh van, trinh luat, sinh vat
vat thong » va thong, vat trong, mat thong
dung manh » duong manh, dung danh, hung manh
hoi hieu » hoi phieu, hoi tieu, moi hieu
toan cao » toan tap
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoi hieu lang - hanh trinh vat thong dung manh ((toan cao) or (toan ban))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoi hieu lang - hanh trinh vat thong dung manh ((toan cao) OR (toan ban))*.