Perhaps you should try some spelling variations:
lam truoc » lam thuoc, nam truoc, lam truong
thien van » thi van
lam truc » nam truc, lam thuoc, lam trung
tinh voi » trinh voi, tinh doi, binh voi
tu sach » thu sach, su sach, te sach
voi cua » hoi cua, doi cua, moi cua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
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 ky nang xa hoi. ((hieu ve) or (thien van)) ((lam truc) OR (lam truoc)) may tinh voi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang xa hoi. ((hieu ve) OR (thien van)) ((lam truc) OR (lam truoc)) may tinh voi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang xa hoi. ((hieu ve) or (thien van)) ((lam truc) OR (lam truoc)) may tinh voi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang xa hoi. ((hieu ve) or (thien van)) ((lam truc) OR (lam truoc)) may tinh voi cua tre*.