Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
ky dang » ky danh
cac tuc » cac tu, cac tac, cac nuoc
cac toc » cac toi, cac nuoc, cac thoi
va danh » va dinh, va dan, va hanh
danh vi » hanh vi, dinh vi, danh di
luu tre » luu tru, cuu tre, luy tre
vi luu » vi lua

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 dang) or (ky nang)) xa hoi. lieu va ((cac tuc) OR (cac toc)) va danh vi luu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((ky dang) OR (ky nang)) xa hoi. lieu va ((cac tuc) OR (cac toc)) va danh vi luu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((ky dang) or (ky nang)) xa hoi. lieu va ((cac tuc) OR (cac toc)) va danh vi luu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((ky dang) or (ky nang)) xa hoi. lieu va ((cac tuc) OR (cac toc)) va danh vi luu tre*.