Perhaps you should try some spelling variations:
hanh dai » hanh tai, hanh dao, vanh dai
van hanh » van thanh, ban hanh, van anh
dang xay » dang van, van xay
te sach » toc sach
cam tuc » cam xuc, cam tu, nam thuc
cua tuc » cua tu, cua thuoc, luat tuc
tuc van » thuc van, truc van, tuc va
hieu ve » hieu va, hieu van
lang xa » lang ha, lang van
cua duc » cua nuoc, cua quoc
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach y ((lang xa) or (dang xay)) hoi. hieu ve cam tuc van hanh dai ((cua tuc) OR (cua duc))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((lang xa) OR (dang xay)) hoi. hieu ve cam tuc van hanh dai ((cua tuc) OR (cua duc)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((lang xa) or (dang xay)) hoi. hieu ve cam tuc van hanh dai ((cua tuc) OR (cua duc))".
• Adding a wildcard symbol may retrieve word variants: te sach y ((lang xa) or (dang xay)) hoi. hieu ve cam tuc van hanh dai ((cua tuc) OR (cua duc))*.