Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
thien van » thi van
cam truc » cau truc, nam truc, lam truoc
xu quang » vu quang, xa quang, x quang
cua tre » cua te, cua triet, dua tren
hanh va » hang va, hanh vi
va hanh » van hanh, va thanh, va danh
truc va » thuc va, thuc vat, trung va
van cam » van nam, van lam, van cau
tu lang » cu lang, tu lanh, xu lang
cuu tre » cau tren, cau treo

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuoc sach ((tu lang) or (xu quang)) xa hoi. thien van cam truc va hanh va ((cua tre) or (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuoc sach ((tu lang) OR (xu quang)) xa hoi. thien van cam truc va hanh va ((cua tre) OR (cuu tre)).
• Adding a wildcard symbol may retrieve word variants: thuoc sach ((tu lang) or (xu quang)) xa hoi. thien van cam truc va hanh va ((cua tre) or (cuu tre))*.