Perhaps you should try some spelling variations:
hong minh » hoang minh, thong minh, khong minh
doan hong » doan huong, doan hung, doan phuong
giai cong » gia cong, giao cong, giai phong
trinh tin » trinh kinh, trinh toan, trinh tu
sach cha » sach nha, sach che, sach ha
tu sach » thu sach, su sach, te sach
hanh ve » hanh vi, hanh va, hanh kem
ve giai » va giai, ve giao, de giai
han ve » phan ve, hang ve, nhan ve
cha ve » cha me, ca ve, pha ve

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 ((han ve) or (hanh ve)) giai doan hong minh ) or ( tu sach cha ve giai cong trinh tin ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( tu sach ((han ve) OR (hanh ve)) giai doan hong minh ) OR ( tu sach cha ve giai cong trinh tin )).
• Adding a wildcard symbol may retrieve word variants: (( tu sach ((han ve) or (hanh ve)) giai doan hong minh ) or ( tu sach cha ve giai cong trinh tin ))*.