Perhaps you should try some spelling variations:
truong toan » truong ton, trong toan, truong tan
thieu xanh » chieu xanh, hieu manh, thien anh
nhung cong » dung cong, thong cong, hang cong
hoc thieu » toc thieu, hoc hien
trinh vat » trinh van, trinh luat, trinh han
luong tai » dung tai, luong va

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 vat) or (sinh vat)) nhung cong ((luong tai) or (truong toan)) cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu xanh - hanh ((trinh vat) OR (sinh vat)) nhung cong ((luong tai) OR (truong toan)) cau.
• Adding a wildcard symbol may retrieve word variants: hoc thieu xanh - hanh ((trinh vat) or (sinh vat)) nhung cong ((luong tai) or (truong toan)) cau*.