Perhaps you should try some spelling variations:
thanh vai » thanh hai, thanh van, thanh tai
ban thanh » ban hanh, ban hang
tai khoa » da khoa, noi khoa
tu sach » thu sach, su sach, te sach
vai cua » dai cua, hai cua, lai cua
dua ban » dia ban, cua ban, qua ban
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, may nang
v nang » va nang, vu nang, van nang
ve cam » ve cham, ve cac, va cam

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 ((y nang) OR (v nang)) tai khoa. hieu ((ve cam) or (va cac)) dua ban thanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((y nang) OR (v nang)) tai khoa. hieu ((ve cam) OR (va cac)) dua ban thanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ((y nang) OR (v nang)) tai khoa. hieu ((ve cam) or (va cac)) dua ban thanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ((y nang) OR (v nang)) tai khoa. hieu ((ve cam) or (va cac)) dua ban thanh vai cua tre*.