Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
han thai » han tai, ban thai, van thai
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
thai va » thai van
y nang » ky nang, ly nang, v nang
luc va » duc va, tuc va
loc va » hoc 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 sach y nang xa hoi. hieu van cham ((luc va) or (loc va)) han thai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach y nang xa hoi. hieu van cham ((luc va) OR (loc va)) han thai va thiet.
• Adding a wildcard symbol may retrieve word variants: tu sach y nang xa hoi. hieu van cham ((luc va) or (loc va)) han thai va thiet*.