Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
thu nang » thu hang, thu bang, tho nang
thi nang » thi cong, ki nang, thi hanh
doanh va » doan va, doanh cua, hanh va
van cham » van chat, van tham, va cham
cham duc » pham duc, cham soc, pham duy
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet

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 ((thu nang) or (thi nang)) xa hoi. hieu van cham duc va ((doanh va) OR (doanh tai)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((thu nang) OR (thi nang)) xa hoi. hieu van cham duc va ((doanh va) OR (doanh tai)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((thu nang) or (thi nang)) xa hoi. hieu van cham duc va ((doanh va) OR (doanh tai)) cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((thu nang) or (thi nang)) xa hoi. hieu van cham duc va ((doanh va) OR (doanh tai)) cua tre*.