Perhaps you should try some spelling variations:
thiet tach » chiet tach, thien hach, thuat tach
truong cua » truong ca, truong quan, truong cao
nhung cong » dung cong, thong cong, hang cong
cong ngang » cong nhan, cong quang, cong lang
hoc thiet » hoc thieu, hoc thuyet, hoc hien
thang cua » thong cua, hang cua, than cua
toan cau » toan ban, toan tap, toan tai
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 thiet tach - hanh ((thang cua) or (truong cua)) nhung cong ngang ((toan cau) OR (toan cao))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thiet tach - hanh ((thang cua) OR (truong cua)) nhung cong ngang ((toan cau) OR (toan cao)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thiet tach - hanh ((thang cua) or (truong cua)) nhung cong ngang ((toan cau) OR (toan cao))".
• Adding a wildcard symbol may retrieve word variants: hoc thiet tach - hanh ((thang cua) or (truong cua)) nhung cong ngang ((toan cau) OR (toan cao))*.