Perhaps you should try some spelling variations:
trinh thiet » trinh viet, trinh thi
thieu sang » chieu sang, thieu khang, thieu quang
hanh trinh » canh tranh, hanh chinh
thiet hung » thuyet hung, viet hung, hiep hung
duong manh » duong van
hoc thieu » toc thieu, hoc hien
cong manh » cong danh, cong thanh, hoang manh
toan cao » toan ban, toan tap

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thieu sang - hanh trinh thiet hung ((cong manh) or (duong manh)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu sang - hanh trinh thiet hung ((cong manh) OR (duong manh)) toan cao*.