Perhaps you should try some spelling variations:
phuong cong » phuong dong, phong cong, phung cong
thieu sang » chieu sang, thieu khang, thieu quang
hanh phan » thanh phan, anh phan, hanh nhan
va phuong » va thuong, cac phuong
hanh han » hanh nhan, hanh san, anh han
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
toan tai » toan tap, doanh tai, toan ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc thieu sang - ((hanh han) or (hanh phan)) va phuong cong dan toan tai~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc thieu sang - ((hanh han) OR (hanh phan)) va phuong cong dan toan tai.
• Adding a wildcard symbol may retrieve word variants: toc thieu sang - ((hanh han) or (hanh phan)) va phuong cong dan toan tai*.