Perhaps you should try some spelling variations:
luu truc » luu tru, cau truc, cuu thuc
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
va hanh » van hanh, va thanh, va danh
luu tre » luu tru, cuu tre, luy tre
ve cao » va cao, ve cac, ve co
ve bao » te bao, va bao
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. hieu ((ve cao) or (ve bao)) duc va hanh vi ((luu tre) or (luu truc))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. hieu ((ve cao) OR (ve bao)) duc va hanh vi ((luu tre) OR (luu truc)).
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu ((ve cao) or (ve bao)) duc va hanh vi ((luu tre) or (luu truc))*.