Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cac lao » ca lao, cac loai, cac giao
sac ky » sai ky
ve cac » va cac, vien cac
lao va » tao va, cao va, bao va
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
vi cau » va cau, ve cau, di cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc ((sac ky) or (cac ky)) nang xa hoi. hieu ve cac lao va dan vi cau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sac ky) OR (cac ky)) nang xa hoi. hieu ve cac lao va dan vi cau tren.
• Adding a wildcard symbol may retrieve word variants: toc ((sac ky) or (cac ky)) nang xa hoi. hieu ve cac lao va dan vi cau tren*.