Perhaps you should try some spelling variations:
dai tren » dat tren, dau tren, dan tren
sach thi » sach thu, sach tai, sach thieu
thi nang » thi cong, ki nang, thi hanh
luc ngan » luc nganh, luc nhan, luat ngan
hang vi » hang va, hanh vi, hang di
cu nhan » ca nhan
tu sach » thu sach, su sach, te sach
nang xa » nang x, lang xa, nang ma
ve cam » ve cham, va cam, ve cai
vi dai » si dai, li dai, vien dai
ve cac » va cac, vien cac

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 thi nang xa hoi. hieu ((ve cam) OR (ve cac)) ((luc ngan) or (cu nhan)) hang vi dai tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach thi nang xa hoi. hieu ((ve cam) OR (ve cac)) ((luc ngan) OR (cu nhan)) hang vi dai tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach thi nang xa hoi. hieu ((ve cam) OR (ve cac)) ((luc ngan) or (cu nhan)) hang vi dai tren*".