Perhaps you should try some spelling variations:
trinh toan » tinh toan, thanh toan, trinh han
hoc thieu » toc thieu, hoc hien
hanh tang » hanh trang, anh tang, hanh tung
hanh mang » nhanh mang, hanh trang, nhanh lang
dung cong » dung trong
chao chu » cho chu, cua chu, cao cho
toan cao » toan ban, toan tap

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: ((hoc thieu) OR (chao chu)) xanh - ((hanh tang) OR (hanh mang)) xay dung cong trinh toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thieu) or (chao chu)) xanh - ((hanh tang) OR (hanh mang)) xay dung cong trinh toan cao~".
• Adding a wildcard symbol may retrieve word variants: ((hoc thieu) or (chao chu)) xanh - ((hanh tang) OR (hanh mang)) xay dung cong trinh toan cao*.