Perhaps you should try some spelling variations:
dang xay » dang van, van xay
van phan » van phong, van thanh, luan phan
phan tai » pham tai, nhan tai, phan thi
hieu va » lieu va, hieu qua
cau duc » cao duc, cau luc, chu duc
duc van » duc va, duc tan, duc manh
tu sac » tu sach, tu cac, tu san
sac ky » cac ky, sai ky
va cau » van cau, va cac, va dau
cuc tu » cuc du, duc tu, cac tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang x) or (dang xay)) hoi. hieu va cau duc van phan tai ((cuc tu) or (luc tu))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang x) OR (dang xay)) hoi. hieu va cau duc van phan tai ((cuc tu) OR (luc tu)).
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang x) or (dang xay)) hoi. hieu va cau duc van phan tai ((cuc tu) or (luc tu))*.