Perhaps you should try some spelling variations:
tru nang » tri nang, truc nano, thi nang
tra nang » thi nang, kha nang, da nang
van bao » van ban, van dao
danh va » doanh va, hanh va, anh va
va danh » va dinh, va dan, va hanh
tu sach » thu sach, su sach, te sach
van cao » van dao, van hao, van cau
va cua » va chua, via cua, ca cua
cua te » cua tu

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 ((tru nang) or (tra nang)) xa hoi. thien ((van cao) OR (van bao)) duc va danh va cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tru nang) OR (tra nang)) xa hoi. thien ((van cao) OR (van bao)) duc va danh va cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((tru nang) or (tra nang)) xa hoi. thien ((van cao) OR (van bao)) duc va danh va cua te".
• Adding a wildcard symbol may retrieve word variants: tu sach ((tru nang) or (tra nang)) xa hoi. thien ((van cao) OR (van bao)) duc va danh va cua te*.