Perhaps you should try some spelling variations:
thien bang » khien bang, thien ban, thien dang
hoc thien » hoc hien, hoc thieu, hoc thiet
trang tai » trang trai, tang tai, trang tri
trang vai » trang va, trang giai, trang trai
dang cong » dung cong
cong san » cong tac
phan cau » phan dau, phan cac, phan lap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc thien bang - hanh ((trang tai) or (trang vai)) dang cong san ((phan cau) OR (phan tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thien bang - hanh ((trang tai) OR (trang vai)) dang cong san ((phan cau) OR (phan tu)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thien bang - hanh ((trang tai) or (trang vai)) dang cong san ((phan cau) OR (phan tu))".
• Adding a wildcard symbol may retrieve word variants: hoc thien bang - hanh ((trang tai) or (trang vai)) dang cong san ((phan cau) OR (phan tu))*.