Perhaps you should try some spelling variations:
nhanh tinh » nhanh thanh, hanh trinh, nhan sinh
toan trong » toan thong, tran trong, gian trong
doi chieu » doi chi, ho chieu, mot chieu
hanh tinh » hanh trinh, thanh tinh, canh tinh
doc hieu » toc thieu, hoc thieu, hoc hien
cong tan » cong tac, cong san, cong thanh
tan toan » tan tran, tap toan, van toan
toan ban » van ban

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((doi chieu) OR (doc hieu)) xanh - ((hanh tinh) or (nhanh tinh)) toan trong cong tan toan ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((doi chieu) OR (doc hieu)) xanh - ((hanh tinh) OR (nhanh tinh)) toan trong cong tan toan ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((doi chieu) OR (doc hieu)) xanh - ((hanh tinh) or (nhanh tinh)) toan trong cong tan toan ban".
• Adding a wildcard symbol may retrieve word variants: ((doi chieu) OR (doc hieu)) xanh - ((hanh tinh) or (nhanh tinh)) toan trong cong tan toan ban*.