Perhaps you should try some spelling variations:
hien xanh » hien nhanh, chieu xanh, hien khanh
hien hanh » dieu hanh
trinh van » trinh han, trinh quan, trinh toan
lang cong » dang cong, bang cong, hang cong
trinh va » trinh vat, trinh ve, trinh vi
cong dan » cong san, cong tan, huong dan
dan toan » van toan, dan than, manh toan
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 ((hien xanh) OR (hien hanh)) - hanh ((trinh va) or (trinh van)) lang cong dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hien xanh) OR (hien hanh)) - hanh ((trinh va) OR (trinh van)) lang cong dan toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hien xanh) OR (hien hanh)) - hanh ((trinh va) or (trinh van)) lang cong dan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((hien xanh) OR (hien hanh)) - hanh ((trinh va) or (trinh van)) lang cong dan toan cao*.