Perhaps you should try some spelling variations:
hoc thuyet » hoc chuyen
nhung cong » dung cong, thong cong, hang cong
hoc thiet » hoc thieu, hoc hien, toc thieu
tung phat » trung phat, hung phat, bung phat
tung pham » hung pham, nhung pham, trung phan
cong dan » cong san, cong tan, huong dan
dan than » dan chan, ban than, van than
than cao » toan cao, thai cao, than cap

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) or (hoc thuyet)) danh - thanh ((tung phat) OR (tung pham)) nhung cong dan than cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((hoc thiet) OR (hoc thuyet)) danh - thanh ((tung phat) OR (tung pham)) nhung cong dan than cao.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((hoc thiet) or (hoc thuyet)) danh - thanh ((tung phat) OR (tung pham)) nhung cong dan than cao".
• Adding a wildcard symbol may retrieve word variants: ((hoc thiet) or (hoc thuyet)) danh - thanh ((tung phat) OR (tung pham)) nhung cong dan than cao*.