Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien anh
hoc thieu » toc thieu, hoc hien
khoan cam » khoa cam, khoan va, phan cam
trinh he » trinh han, trinh hoa, trinh thi
trinh do » trinh ky
long dan » long doan, nong dan, long van
cong dan » cong san, cong tan, huong dan

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 - canh ((trinh he) or (trinh do)) thanh ((long dan) OR (cong dan)) khoan cam~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - canh ((trinh he) OR (trinh do)) thanh ((long dan) OR (cong dan)) khoan cam.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu xanh - canh ((trinh he) or (trinh do)) thanh ((long dan) OR (cong dan)) khoan cam".
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - canh ((trinh he) or (trinh do)) thanh ((long dan) OR (cong dan)) khoan cam*.