Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
hang tai » hang va, dung tai
su viet » so viet
nang xa » nang x, lang xa, nang ma
van cam » van nam, van lam, van cau
truc va » thuc va, trung va
han tai » nhan tai, van tai, toan tai
te ban » te bao
ban ky » van ky, dan ky

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

• Performing a fuzzy search may retrieve terms with similar spellings: te ban ky nang xa hoi. hieu van cam ((truc va) or (thuc vat)) ((han tai) OR (hang tai)) su viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ban ky nang xa hoi. hieu van cam ((truc va) OR (thuc vat)) ((han tai) OR (hang tai)) su viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ban ky nang xa hoi. hieu van cam ((truc va) or (thuc vat)) ((han tai) OR (hang tai)) su viet*".