Perhaps you should try some spelling variations:
xach tay » canh tay
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
cham hoc » cham soc, chat hoc, cham hoi
nang xa » lang xa, nang ma, mang xa
han tai » hang tai, nhan tai, van tai
va han » va phan, van han, va hanh
tai va » thai va, mai va, tri 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: tu ((xach tay) or (sach y)) ((nang xa) or (nang x)) hoi. hieu van cham hoc va han tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((xach tay) OR (sach y)) ((nang xa) OR (nang x)) hoi. hieu van cham hoc va han tai va thiet.
• Adding a wildcard symbol may retrieve word variants: tu ((xach tay) or (sach y)) ((nang xa) or (nang x)) hoi. hieu van cham hoc va han tai va thiet*.