Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
thanh vi » hanh vi, thanh va, thanh ve
cau tren » cu tren, ca tren, cau treo
dau tren » dau tien, dat tren, dau tieng
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
thi van » thi lan, thi hanh, thi nang
nam tu » nam thu, nam thuc
x hoi » xa hoi, o hoi, x ho

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 ky nang x hoi. ((thien van) or (thi van)) nam tu va thanh vi ((cau tren) OR (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. ((thien van) OR (thi van)) nam tu va thanh vi ((cau tren) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. ((thien van) or (thi van)) nam tu va thanh vi ((cau tren) OR (dau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. ((thien van) or (thi van)) nam tu va thanh vi ((cau tren) OR (dau tren))*.