Perhaps you should try some spelling variations:
thien tinh » khien tinh, thien minh, tien tinh
thong cong » trong cong, tong cong, thong thong
hien tinh » khien tinh, bien tinh, dien tinh
trang cua » tang cua, trung cua, thang cua
tranh cua » doanh cua, manh cua
cong tan » cong tac, cong san, cong thanh
tan chan » dan chan, ban chan, can chan
chan cau » phan cau, can cau, chinh cau

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

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