Perhaps you should try some spelling variations:
nang xa » lang xa, nang ma, mang xa
hieu vu » hieu va, hieu ve, hieu su
xuc van » duc van, luc van, vuc van
van han » van hanh, van phan, van nhan
vu sac » vu sach, vu san, va sac
sac ky » cac ky, sai ky
vu cam » vu cham, vu cao, va cam
tai va » thai va, tri va, dai va
thiet » thieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: vu sac ky ((nang xa) or (nang x)) hoi. hieu vu cam xuc van han ((tai va) OR (mai va)) thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sac ky ((nang xa) OR (nang x)) hoi. hieu vu cam xuc van han ((tai va) OR (mai va)) thiet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sac ky ((nang xa) or (nang x)) hoi. hieu vu cam xuc van han ((tai va) OR (mai va)) thiet".
• Adding a wildcard symbol may retrieve word variants: vu sac ky ((nang xa) or (nang x)) hoi. hieu vu cam xuc van han ((tai va) OR (mai va)) thiet*.