Perhaps you should try some spelling variations:
cac nuoc » cap nuoc, hoc nuoc, dat nuoc
su sach » so sach, vu sach
ly nang » ky nang, ly hang, ly vang
hang vi » hang va, hanh vi, khang voi
hang di » hang doi, hang dien, hang dich
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, v nang, may nang

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ((y nang) or (ly nang)) xa hoi. lieu va cac nuoc va ((hang vi) OR (hang di)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((y nang) OR (ly nang)) xa hoi. lieu va cac nuoc va ((hang vi) OR (hang di)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((y nang) or (ly nang)) xa hoi. lieu va cac nuoc va ((hang vi) OR (hang di)) cua tre".
• Adding a wildcard symbol may retrieve word variants: su sach ((y nang) or (ly nang)) xa hoi. lieu va cac nuoc va ((hang vi) OR (hang di)) cua tre*.