Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
trinh quan » tinh quang, trinh luat, trinh han
hoc thieu » toc thieu, hoc hien
trinh cua » tinh cua, trinh luat, trinh luan
cong cong » trong cong, dung cong, dang cong
tap toan » tap doan, tap quan, bai 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 thieu xanh - hanh ((trinh cua) or (trinh quan)) ((cong cong) OR (cong dong)) tap toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - hanh ((trinh cua) OR (trinh quan)) ((cong cong) OR (cong dong)) tap toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - hanh ((trinh cua) or (trinh quan)) ((cong cong) OR (cong dong)) tap toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - hanh ((trinh cua) or (trinh quan)) ((cong cong) OR (cong dong)) tap toan cao*.