Perhaps you should try some spelling variations:
hien xanh » hien hanh, hien nhanh, chieu xanh
trinh vat » trinh van, trinh luat, sinh vat
lang cong » dang cong, bang cong, hang cong
trinh va » trinh van, 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 - hanh ((trinh va) OR (trinh vat)) lang cong dan toan cao~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - hanh ((trinh va) OR (trinh vat)) lang cong dan toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - hanh ((trinh va) OR (trinh vat)) lang cong dan toan cao*.