Perhaps you should try some spelling variations:
thieu xanh » chieu xanh, hieu manh, thien danh
thien anh » thien danh, tien anh, thien thanh
hanh sinh » hanh tinh, hanh dinh, hinh sinh
chong van » thong van, phong van, chong va
hong van » hoang van, thong van, phong van
toan cao » toan ban, toan tap
sinh va » sinh vat, tinh va, dinh van

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) or (thien anh)) - hanh sinh va nhung ((chong van) OR (hong van)) toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((thieu xanh) OR (thien anh)) - hanh sinh va nhung ((chong van) OR (hong van)) toan cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((thieu xanh) or (thien anh)) - hanh sinh va nhung ((chong van) OR (hong van)) toan cao".
• Adding a wildcard symbol may retrieve word variants: hoc ((thieu xanh) or (thien anh)) - hanh sinh va nhung ((chong van) OR (hong van)) toan cao*.