Perhaps you should try some spelling variations:
thieu manh » hieu manh, tien manh, trieu minh
thong cong » trong cong, tong cong, thong thong
hoc thieu » toc thieu, hoc hien
trinh vat » trinh van, trinh luat, sinh vat
trinh va » trinh van, trinh vi, trinh han
trinh ve » trinh he, trinh vi, trinh viet
cong dan » cong san, cong tan, huong dan
dan chan » dan gian, dan ca, van chat
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 thieu manh - canh ((((trinh va) OR (trinh vat))) or (trinh ve)) thong cong dan chan cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc thieu manh - canh ((((trinh va) OR (trinh vat))) OR (trinh ve)) thong cong dan chan cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc thieu manh - canh ((((trinh va) OR (trinh vat))) or (trinh ve)) thong cong dan chan cau".
• Adding a wildcard symbol may retrieve word variants: hoc thieu manh - canh ((((trinh va) OR (trinh vat))) or (trinh ve)) thong cong dan chan cau*.